Mitsubishi FUEL, MPI 4G6, MPI 6A1 USER MANUAL

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Page 1

FUEL

CONTENTS

MULTIPOINT FUEL INJECTION (MPI) 13A....................................

GASOLINE DIRECT INJECTION (GDI) 13I...................................

13A-1

Page 2

13A-2

MULTIPOINT FUEL

INJECTION (MPI)

CONTENTS

MULTIPOINT FUEL INJECTION (MPI)

<4G6> 3..............................

GENERAL 3...............................

Outline of Changes 3........................

GENERAL INFORMATION 3................

Self-diagnosis Function 3.....................

General Specifications 3.....................

SERVICE SPECIFICATIONS 3..............

TROUBLESHOOTING 4....................

Diagnosis Function 4........................

Fail-safe Function Reference Table 7..........

Inspection Chart for Diagnosis Codes 8.......

Inspection Procedure Classified by Diagnosis

Code 10....................................

Inspection Chart for Trouble Symptoms 45.....

Inspection Procedure for Trouble Symptoms

Data List Reference Table 75.................

Actuator Test Reference Table 80.............

Check at the Engine-ECU Terminals 81.......

Inspection Procedure Using an Analyzer 88....

ON-VEHICLE SERVICE 89.................

Oxygen Sensor Check 89....................

MULTIPOINT FUEL INJECTION (MPI)

<6A1> 91.............................

GENERAL 91..............................

Outline of Changes 91.......................

GENERAL INFORMATION 91...............

Self-diagnosis Function 91....................

General Specifications 91....................

Multipoint Fuel Injection System Diagram 92...

SERVICE SPECIFICATIONS 93.............

TROUBLESHOOTING 94...................

Diagnosis Function 94.......................

Fail-safe Function Reference Table 98.........

Inspection Chart for Diagnosis Codes 99......

Inspection Procedure Classified by Diagnosis

Code 101...................................

Inspection Chart for Trouble Symptoms 145....

46.........................................

Inspection Procedure for Trouble Symptoms

146........................................

Data List Reference Table 176................

Actuator Test Reference Table 183............

Check at the Engine-ECU Terminals 185......

Inspection Procedure Using an Analyzer 192...

ON-VEHICLE SERVICE 193...............

Oxygen Sensor Check 193...................

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MPI <4G6> -

General/General Information/Service Specifications

13A-3

MULTIPOINT FUEL INJECTION (MPI) <4G6>

GENERAL

OUTLINE OF CHANGES

Due to the changes shown below, the service procedures regarding the different description from the previous version have been established.

On-board Diagnostics System has been adopted to expand the diagnostic items and to change diagnosis

code numbering system. The engine-ECU has been changed. <Vehicles with M/T>

An engine-A/T-ECU has been adopted. <Vehicles with A/T>

An ignition failure sensor has been adopted.

The injector has been changed.

The oxygen sensor has been changed.

GENERAL INFORMATION

SELF-DIAGNOSIS FUNCTION

Following functions have been added.

The engine-ECU records the engine operating condition when the diagnosis code is set. This data

is called “freeze frame” data. It can be read by using the MUT-II, and can be used in simulation tests for troubleshooting.

GENERAL SPECIFICATIONS

Items Specifications

Engine-ECU <M/T> Identification model No. E2T67693

Engine-A/T-ECU <A/T> Identification model No. E6T30571

Actuators Injector identification mark CDH240

SERVICE SPECIFICATIONS

Items Standard value

Oxygen sensor output voltage V 0.6 - 1.0

Oxygen sensor heater coil resistance (at 20_C) front 4.5 - 8.0

rear 11 - 18

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13A-4

MPI <4G6> -

TROUBLESHOOTING

DIAGNOSIS FUNCTION

ENGINE WARNING LAMP (CHECK ENGINE LAMP)

Engine warning lamp (check engine lamp)

Engine warning lamp inspection items

Code No. Diagnosis item

- Engine-ECU <M/T> or engine-A/T-ECU <A/T>

P0100 Air flow sensor system

P0105 Barometric pressure sensor system

code output. However, the warning lamp will illuminate as bulb check for five seconds whenever the ignition switch is turned to the ON position.

Troubleshooting

P0110 Intake air temperature sensor system

P0115 Engine coolant temperature sensor system

P0120 Throttle position sensor system

P0125 Feedback system

P0130 Oxygen sensor (front) system <sensor 1>

P0135 Oxygen sensor heater (front) system <sensor 1>

P0136 Oxygen sensor (rear) system <sensor 2>

P0141 Oxygen sensor heater (rear) system <sensor 2>

P0170 Abnormal fuel system

P0201 No. 1 injector system

P0202 No. 2 injector system

P0203 No. 3 injector system

P0204 No. 4 injector system

P0300

Ignition coil (power transistor) system

P0301 No. 1 cylinder misfire detected

P0302 No. 2 cylinder misfire detected

P0303 No. 3 cylinder misfire detected

P0304 No. 4 cylinder misfire detected

P0335 Crank angle sensor system

P0340 Camshaft position sensor system

Page 5

MPI <4G6> -

Code No. Diagnosis item

P0403 EGR valve system

P0420 Catalyst malfunction

P0443 Purge control solenoid valve system

P0505 Idle speed control system

P0510 Idle position switch system

P0551 Power steering fluid pressure switch system

NOTE

1. If the engine warning lamp illuminates because of a malfunction of the engine-ECU <M/T> or engine-A/T-ECU <A/T>, communication between MUT-IIand the engine-ECU <M/T> or engine-A/T-ECU <A/T> is impossible. In this case, the diagnosis code cannot be read.

2. After the engine-ECU <M/T> or engine-A/T-ECU <A/T> has detected a malfunction, the engine warning lamp illuminates when the engine is next turned on and the same malfunction is re-detected. However, for items marked with a “L” in the diagnosis code number column, the engine warning lamp illuminates only on the first detection of the malfunction.

3. After the engine warning lamp illuminates, it will be switched off under the following conditions. (1) When the engine-ECU <M/T> or engine-A/T-ECU <A/T> monitored the power train malfunction

three times* and met set condition requirements, it detected no malfunction. *: In this case, “one time” indicates from engine start to stop.

(2) For misfiring malfunction, when driving conditions (engine speed, engine coolant temperature,

etc.) are similar to those when the malfunction was first recorded.

4. Sensor 1 indicates the sensor mounted at a position closest to the engine, and sensor 2 indicates the sensor mounted at the position second closest to the engine.

Troubleshooting

13A-5

METHOD OF READING AND ERASING DIAGNOSIS CODES

Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points.

DIAGNOSIS USING DIAGNOSIS 2 MODE

1. Switch the diagnosis mode of the engine control unit to DIAGNOSIS 2 mode using the MUT-II.

2. Carry out a road test.

3. Take a reading of the diagnosis code and repair the problem location.

4. Turn the ignition switch to OFF and then back to ON again.

NOTE By turning the ignition switch to OFF, the ENGINE-ECU will switch the diagnosis mode from DIAGNOSIS 2 mode to DIAGNOSIS 1 mode.

5. Erase the diagnosis codes.

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13A-6

MPI <4G6> -

INSPECTION USING MUT-IIDATA LIST AND ACTUATOR TESTING

1. Carry out inspection by means of the data list and the

2. After repairing, re-check using the MUT-IIand check that

3. Erase the diagnosis code memory.

4. Remove the MUT-II, and then start the engine again and

FREEZE FRAME DATA

When the engine-ECU <M/T> or engine-A/T-ECU <A/T> detects a malfunction and stores a diagnosis code, it also stores a current status of the engine. This function is called “Freeze frame data.” By analyzing this “freeze frame” data with the MUT-II, an effective troubleshooting can be performed. The display items of freeze frame data are shown below.

Troubleshooting

actuator test function. If there is an abnormality, check and repair the chassis harnesses and components.

the abnormal input and output have returned to normal as a result of the repairs.

carry out a road test to confirm that the problem has disappeared.

Display item list

Data item Unit

Engine coolant temperature sensor _C

Engine speed r/min

Vehicle speed km/h

Long-term fuel compensation (long-term fuel trim)

Short-term fuel compensation (short-term fuel trim)

Fuel control condi- Open loop OL tion

Closed loop CL

Open loop owing to drive condition

Open loop owing to system malfunction

Closed loop based on one oxygen sensor

OL-DRV.

OL-SYS.

CL-H02S

Calculation load value %

Diagnosis code during data recording -

NOTE If malfunctions have been detected in multiple systems, store one malfunction only, which has been detected first.

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MPI <4G6> -

Troubleshooting

13A-7

READINESS TEST STATUS

The engine-ECU <M/T> or engine-A/T-ECU <A/T> monitors the following main diagnosis items, judges if these items are in good condition or not, and the stores its history. This history can be read out by using MUT-II. (If the ECU has judged a item before, the MUT-IIdisplays “Complete.”) In addition, if diagnosis codes are erased or the battery cable is disconnected, this history will also be erased (the memory will be reset).

Catalyst: P0420

Oxygen sensor: P0130

Oxygen sensor heater: P0135, P0141

FAIL-SAFE FUNCTION REFERENCE TABLE

When the main sensor malfunctions are detected by the diagnosis function, the vehicle is controlled by means of the pre-set control logic to maintain safe conditions for driving.

Malfunctioning item Control contents during malfunction

Air flow sensor 1. Uses the throttle position sensor signal and engine speed signal (crank angle sensor

signal) to take reading of the basic injector drive time and basic ignition timing from the pre-set mapping.

2. Fixes the ISC servo in the appointed position so idle control is not performed.

Intake air temperature sensor

Throttle position sensor (TPS)

Engine coolant temperature sensor

Camshaft position sensor

Barometric pressure sensor

Detonation sensor Switches the ignition timing from ignition timing for super petrol to ignition timing for standard

Ignition coil, power transistor

Oxygen sensor (front) Air/fuel ratio feedback control (closed loop control) is not performed.

Controls as if the intake air temperature is 25_C.

No increase in fuel injection amount during acceleration due to the throttle position sensor signal.

Controls as if the engine coolant temperature is 80_C.

Injects fuel to all cylinders simultaneously. (However, after the ignition switch is turned to ON, the No. 1 cylinder top dead centre is not

detected at all.)

Controls as if the barometric pressure is 101 kPa.

petrol.

Cuts off the fuel supply to cylinders with an abnormal ignition.

Oxygen sensor (rear) Performs the feedback control (closed loop control) of the air/fuel ratio by using only the

signal of the oxygen sensor (front) installed on the front of the catalytic converter.

Alternator FR terminal Does not control the output of the alternator according to an electrical load. (works as a

normal alternator)

Misfiring If the detected misfiring causes damage to the catalyst, the misfiring cylinder will be shut

down.

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13A-8

MPI <4G6> -

Troubleshooting

INSPECTION CHART FOR DIAGNOSIS CODES

Code No. Diagnosis item Reference page

P0100 Air flow sensor system 13A-10

P0105 Barometric pressure sensor system 13A-12

P0110 Intake air temperature sensor system 13A-14

P0115 Engine coolant temperature sensor system 13A-16

P0120 Throttle position sensor system 13A-18

P0125 Feedback system 13A-20

P0130 Oxygen sensor (front) system <sensor 1> 13A-21

P0135 Oxygen sensor heater (front) system <sensor 1> 13A-23

P0136 Oxygen sensor (rear) system <sensor 2> 13A-24

P0141 Oxygen sensor heater (rear) system <sensor 2> 13A-26

P0170 Abnormal fuel system 13A-27

P0201 No. 1 injector system 13A-28

P0202 No. 2 injector system 13A-28

P0203 No. 3 injector system 13A-28

P0204 No. 4 injector system 13A-28

P0300

P0301 No. 1 cylinder misfire detected 13A-31

P0302 No. 2 cylinder misfire detected 13A-31

P0303 No. 3 cylinder misfire detected 13A-31

P0304 No. 4 cylinder misfire detected 13A-31

P0325 Detonation sensor system 13A-32

P0335 Crank angle sensor system 13A-32

P0340 Camshaft position sensor system 13A-34

P0403 EGR valve system 13A-36

P0420 Catalyst malfunction 13A-37

Ignition coil (power transistor) system 13A-29

P0443 Purge control solenoid valve system 13A-38

P0500 Vehicle speed sensor system 13A-39

P0505 Idle speed control system 13A-39

P0510 Idle position switch system 13A-41

P0551 Power steering fluid pressure switch system 13A-42

P1500 Alternator FR terminal system 13A-43

P1610 Immobilizer system 13A-44

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MPI <4G6> -

NOTE

1. Do not replace the engine-ECU <M/T> or engine-A/T-ECU <A/T> until a through terminal check reveals there are no short/open circuit.

2. Check that the engine-ECU <M/T> or engine-A/T-ECU <A/T> earth circuit is normal before checking for the cause of the problem.

3. After the engine-ECU <M/T> or engine-A/T-ECU <A/T> has detected a malfunction, a diagnosis code is recorded the next time the engine is started and the same malfunction is re-detected. However, for items marked with a “L”, the diagnosis code is recorded on the first detection of the malfunction.

4. Sensor 1 indicates the sensor mounted at a position closest to the engine, and sensor 2 indicates the sensor mounted at the position second closest to the engine.

Troubleshooting

13A-9

Page 10

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MPI <4G6> -

Troubleshooting

INSPECTION PROCEDURE CLASSIFIED BY DIAGNOSIS CODE

Code No. P0100 Air flow sensor system Probable cause

Range of Check

Engine speed: 500 r/min or more

Set Conditions

The sensor output frequency is 3.3 Hz or less for four seconds.

Malfunction of air flow sensor

Open or short circuit in air flow sensor circuit or

loose connector contact Malfunction of engine-ECU <M/T>

Malfunction of engine-A/T-ECU <A/T>

MUT-IIData list

12 Air flow sensor (Refer to

P.13A-75, DATA LIST REFERENCE TABLE.)

Check the following connector:

B-12

Measure at air flow sensor connector B-12.

Disconnect the connector and

measure at the harness side.

(1) Voltage between terminal 3 and

earth (Ignition switch: ON)

OK:

(2) Voltage between terminal 4 and

(3) Resistance between terminal 5

To the next page

4.8 - 5.2 V

earth (Ignition switch: ON)

OK:

System voltage

and earth

OK:

2Wor less

(1) NG

(2) NG

(3) NG

Transient malfunction (Refer to GROUP 00 - Points to Note for Intermittent Malfunctions.)

Repair

Measure at engine-ECU connector C-40 <M/T> or engine-A/T-ECU connector C-176 <A/T>.

Measure the voltage at the

engine-ECU terminal <M/T> or engine-A/T-ECU terminal <A/T>. Ignition switch: ON

Voltage between terminal 90

<M/T>, 65 <A/T> and earth

OK:

4.8 - 5.2 V

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness between the air flow sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the trouble symptoms.

Check the following connector:

C-31

Check the harness between the air flow sensor and the engine control relay, and repair if necessary.

Check the following connectors:

C-40 <M/T>, C-176 <A/T>

Check the harness between the air flow sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the trouble symptoms.

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness between the air flow sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Repair

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Repair

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Repair

Page 11

From the previous page

Measure at air flow sensor connector B-12.

Use test harness (MB991709) to

connect the connector, and measure at the pick-up harness. Ignition switch: ON

Voltage between terminal 7 and

earth

OK:

7-8V

Measure at air flow sensor connector B-12.

Use test harness (MB991709) to

connect the connector, and measure at the pick-up harness. Voltage between terminal 7 and

earth

OK:

Engine: Idling 0-1V Engine speed: 3,000 r/min 6-9V

Measure the output waveform at air flow sensor connector B-12 (by using an analyzer).

Use test harness (MB991709) to

connect the connector, and measure at the pick-up harness. Engine: Idling

Voltage between terminal 3 and

earth

OK:

Waveforms should be displayed on P.13A-88 (Inspection Procedure Using an Analyzer) and noise should not be displayed in the waveform.

Check the trouble symptoms.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

MPI <4G6> -

Check the following connector:

C-34 <M/T>, C-177 <A/T>

Check the harness between the air flow sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Replace the air flow sensor.

Check the following connector:

C-34 <M/T>, C-177 <A/T>

Check the harness between the air flow sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the trouble symptoms.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Replace the air flow sensor.

Check the trouble symptoms.

Check the following connectors:

C-40 <M/T>, C-176 <A/T>, C-31

Check the harnesses between the air flow sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T> and between the air flow sensor and the engine control relay, and repair if necessary.

Troubleshooting

13A-11

Repair

Page 12

13A-12

MPI <4G6> -

Troubleshooting

Code No. P0105 Barometric pressure sensor system Probable cause

Range of Check

Two seconds have passed since the ignition switch is turned ON or the

engine starting process is completed. Battery voltage: 8 V or more

Set Conditions

The sensor output voltage is 4.5 V or more for four seconds (equivalent to

114 kPa of barometric pressure)

The sensor output voltage is 0.2 V or less (equivalent to 53 kPa of

barometric pressure)

Malfunction of barometric pressure sensor

Open or short circuit in barometric pressure

sensor circuit or loose connector contact Malfunction of engine-ECU <M/T>

Malfunction of engine-A/T-ECU <A/T>

MUT-IIData list

25 Barometric pressure sensor

(Refer to P.13A-75, DATA LIST REFERENCE TABLE.)

Check the following connector:

B-12

Measure at air flow sensor connector B-12.

Disconnect the connector and

measure at the harness side.

(1) Voltage between terminal 1 and

earth (Ignition switch: ON)

OK:

(2) Resistance between terminal 5

4.8 - 5.2 V

and earth

OK:

2Wor less

(1) NG

(2) NG

Transient malfunction (Refer to GROUP 00 - Points to Note for Intermittent Malfunctions.)

Repair

Measure at engine-ECU connector C-40 <M/T> or engine-A/T-ECU connector C-176 <A/T>.

Measure the voltage at the

engine-ECU terminal <M/T> or engine-A/T-ECU terminal <A/T>. Ignition switch: ON

Voltage between terminal 81

<M/T>, 46 <A/T> and earth

OK:

4.8 - 5.2 V

Check the following connectors:

C-40 <M/T>, C-176 <A/T>, C-47 <RHD>

Check the harness between the air flow sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the trouble symptoms.

Check the following connector:

C-40 <M/T>, C-176<A/T>

Check the following connectors:

C-40 <M/T>, C-176 <A/T>, C-47 <RHD>

Check the harness between the air flow sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Repair

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Repair

To the next page

Check the harness between the air flow sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the trouble symptoms.

Repair

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Page 13

From the previous page

Measure at air flow sensor connector B-12.

Connect connector terminals No.

1, No. 2 and No. 5 only by using test harness (MB991709), and measure at the pick-up harness. Ignition switch: ON

(1) Voltage between terminal 1 and

earth

OK:

(2) Voltage between terminal 2 and

(3) Voltage between terminal 5 and

4.8 - 5.2 V

earth

OK:

Altitude 0 m: 3.7 - 4.3 V Altitude 1,200 m:

3.2 - 3.8 V

earth

OK:

0.5 V or less

MPI <4G6> -

(1) NG

(3) NG

(2) NG

Check the following connectors:

C-40 <M/T>, C-176 <A/T>, C-47 <RHD>

Check the harness between the air flow sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Replace the air flow sensor.

Check the trouble symptoms.

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness between the air flow sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Troubleshooting

13A-13

Repair

Measure at engine-ECU connector C-40 <M/T> or engine-A/T-ECU connector C-176 <A/T>.

Measure the voltage at the

engine-ECU terminal. Ignition switch: ON

Voltage between terminal 85

<M/T>, 55 <A/T> and earth

OK:

Altitude 0 m: 3.7 - 4.3 V Altitude 1,200 m:

3.2 - 3.8 V

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness between the air flow sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the trouble symptoms.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Repair

Page 14

13A-14

MPI <4G6> -

Troubleshooting

Code No. P0110 Intake air temperature sensor system Probable cause

Range of Check

Two seconds have passed since the ignition switch is turned ON or the

engine starting process is completed.

Set Conditions

The sensor output voltage is 4.6 V or more for four seconds (equivalent to

-45_C of intake air temperature)

The sensor output voltage is 0.2 V or more for four seconds (equivalent to

125_C of intake air temperature)

Malfunction of intake air temperature sensor

Open or short circuit in intake air temperature

sensor or loose connector contact Malfunction of engine-ECU <M/T>

Malfunction of engine-A/T-ECU <A/T>

MUT-IIData list

13 Intake air temperature sensor

OK:

Roughly the same as ambient temperature.

Check the intake air temperature sensor itself. (Refer to P.13A-90*.)

Check the following connector:

B-12

Measure at air flow sensor connector B-12.

Disconnect the connector and

measure at the harness side.

(1) Resistance between terminal 5

and earth

OK:

(2) Voltage between terminal 6 and

2Wor less

earth (Ignition switch: ON)

OK:

4.8 - 5.2 V

(1) NG

(2) NG

Transient malfunction (Refer to GROUP 00 - Points to Note for Intermittent Malfunctions.)

Repair

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness between the air flow sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the trouble symptoms.

Measure at engine-ECU connector C-40 <M/T> or engine-A/T-ECU connector C-176 <A/T>.

Measure the voltage at the

engine-ECU terminal <M/T> or engine-A/T-ECU terminal <A/T>. Disconnect connector B-12.

Ignition switch: ON

Voltage between terminal 62

<M/T>, 64 <A/T> and earth

OK:

4.8 - 5.2 V

Repair

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness between the air flow sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Repair

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness between the air flow sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the trouble symptoms.

To the next page

NOTE: *: Refer to the ’97 GALANT Workshop Manual (Pub. No. PWDE9611)

Repair

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Page 15

From the previous page

Measure at air flow sensor connector B-12.

Use the test harness (MB991709)

to connect only terminals 5 and 6, and then measure at the pick-up harness. Ignition switch: ON

Voltage between terminal 6 and

earth

OK:

Ambient temperature 0_C:

3.2 - 3.8 V Ambient temperature 20_C:

2.3 - 2.9 V Ambient temperature 40_C:

1.5 - 2.1 V Ambient temperature 80_C:

0.4 - 1.0 V OK

Check the trouble symptoms.

MPI <4G6> -

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness between the air flow sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Troubleshooting

13A-15

Repair

Page 16

13A-16

MPI <4G6> -

Troubleshooting

Code No. P0115 Engine coolant temperature sensor system

Range of Check

Engine: Two seconds after the engine has been started

Set Conditions

The sensor output voltage is 4.6 V or more for four seconds (equivalent to

-45_C or lower of engine coolant temperature)

The sensor output voltage is 0.1 V or less for four seconds (equivalent to

140_C or higher of engine coolant temperature)

Range of Check

Engine: After starting

Set Conditions

The engine coolant temperature has reduced from over 40_C to less than

40_C, and that condition has lasted for five minutes or more.

MUT-IIData list

21 Engine coolant temperature

sensor

OK:

When the engine is cold, the temperature is roughly the same as ambient temperature. If warm, it is 80 120_C.

Measure at engine coolant temperature sensor connector B-33.

Disconnect the connector and

measure at the harness side. Resistance between terminals 1

and 2

OK:

At 20_C of engine coolant temperature: 2.1 - 2.7 k At 80_C of engine coolant temperature: 0.26 - 0.36 k

Transient malfunction (Refer to GROUP 00 - Points to Note for Intermittent Malfunctions.)

Replace

Probable cause

Malfunction of engine coolant temperature sensor

Open or short circuit in the engine coolant

temperature sensor circuit or loose connector contact Malfunction of engine-ECU <M/T>

Malfunction of engine-A/T-ECU <A/T>

Check the following connector:

B-33

To the next page

Repair

Page 17

From the previous page

Measure at engine coolant temperature sensor connector B-33.

Disconnect the connector and

measure at the harness side.

(1) Voltage between terminal 1 and

earth (Ignition switch: ON)

OK:

(2) Resistance between terminal 2

Measure at engine coolant temperature sensor connector B-33.

D D

Check the trouble symptoms.

4.8 - 5.2 V

and earth

OK:

2Wor less

Use test harness (MB991658) to connect the connector, and measure at the pick-up harness. Ignition switch: ON Voltage between terminal 1 and earth

OK:

At 0_C of engine coolant temperature: 3.2 - 3.8 V At 20_C of engine coolant temperature: 2.3 - 2.9 V At 40_C of engine coolant temperature: 1.3 - 1.9 V At 80_C of engine coolant temperature: 0.3 - 0.9 V

MPI <4G6> -

(1) NG

(2) NG

Measure at engine-ECU connector C-40 <M/T> or engine-A/T-ECU connector C-176 <A/T>.

D D D

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness wire between the engine coolant temperature sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the trouble symptoms.

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness wire between the engine coolant temperature sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the trouble symptoms.

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Troubleshooting

Measure the voltage at the engine-ECU terminal <M/T> or engine-A/T-ECU terminal <A/T>. Disconnect connector B-33. Ignition switch: ON Voltage between terminal 83 <M/T>, 44 <A/T> and earth

OK:

4.8 - 5.2 V

Check the engine coolant temperature sensor. (Refer to P.13A-90*.)

Check the harness wire between the engine coolant temperature sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

13A-17

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness wire between the engine coolant temperature sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Repair

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Repair

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Repair

NOTE: *: Refer to the ’97 GALANT Workshop Manual (Pub. No. PWDE9611)

Page 18

13A-18

MPI <4G6> -

Troubleshooting

Code No. P0120 Throttle position sensor system Probable cause

Range of Check

Excluding two seconds after the ignition switch is turned ON or immediately

after the engine starts.

Set Conditions

When the idle position switch is ON, the sensor output voltage is 2 V or

more for 4 seconds

The sensor output voltage is 0.2 V or less for 4 seconds

Malfunction of throttle position sensor

Improper connector contact, open circuit or

short-circuited harness wire Improper “ON” state of idle position switch

Short circuit of the idle position switch signal line

Malfunction of engine-ECU <M/T>

Malfunction of engine-A/T-ECU <A/T>

MUT-IIData list

14 Throttle position sensor

(Refer to P.13A-75, DATA LIST REFERENCE TABLE.)

Check the throttle position sensor. (Refer to P.13A-91*.)

Check the following connector:

B-07

Measure at throttle position sensor connector B-07.

Disconnect the connector and

measure at the harness side.

(1) Voltage between terminal 1 and

earth (Ignition switch: ON)

OK:

(2) Resistance between terminal 4

To the next page

4.8 - 5.2 V

and earth

OK:

2Wor less

(1) NG

(2) NG

Transient malfunction (Refer to GROUP 00 - Points to Note for Intermittent Malfunctions.)

Replace

Repair

Measure at engine-ECU connector C-40 <M/T> or engine-A/T-ECU connector C-176 <A/T>.

Measure the voltage at the

engine-ECU <M/T> or engine-A/T-ECU <A/T> connector terminals. Ignition switch: ON

Voltage between terminal 81 and

earth

OK:

4.8 - 5.2 V NG

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness wire between the throttle position sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the trouble symptoms.

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness wire between the throttle position sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the trouble symptoms.

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness wire between the throttle position sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Repair

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Repair

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Repair

NOTE: *: Refer to the ’97 GALANT Workshop Manual (Pub. No. PWDE9611)

Page 19

From the previous page

Measure at throttle position sensor connector B-07.

Use test harness (MB991536) to

connect the connector, and measure at the pick-up harness. Ignition switch: ON

(1) Voltage between terminal 1 and

earth

OK:

(2) Voltage between terminal 4 and

(3) Voltage between terminal 2 and

Measure at engine-ECU connector C-40 <M/T> or engine-A/T-ECU connector C-175 <A/T>.

D D

4.8 - 5.2 V

earth

OK:

0.5 V or less

earth

OK:

Accelerator pedal fully released: 0.3 - 1.0 V Accelerator pedal fully depressed: 4.5 - 5.5 V

Measure voltage at the engine-ECU terminal. Ignition switch: ON Voltage between terminal 84 <M/T>, 78 <A/T> and earth

OK:

Accelerator pedal fully released: 0.3 - 1.0 V Accelerator pedal fully depressed: 4.5 - 5.5 V

MPI <4G6> -

(1) NG

(2) NG

(3) NG

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness wire between the throttle position sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Adjust the throttle position sensor. (Refer to P.13A-81*.)

Check the following connector:

C-40 <M/T>, C-175 <A/T>

Check the harness wire between the throttle position sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Check the following connector:

C-40 <M/T>, C-175 <A/T>

Check the harness wire between the throttle position sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Check the following connector:

C-40 <M/T>, C-175<A/T>

Check the trouble symptoms.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Troubleshooting

13A-19

Repair

NOTE: *: Refer to the ’97 GALANT Workshop Manual (Pub. No. PWDE9611)

Page 20

13A-20

MPI <4G6> -

Troubleshooting

Code No. P0125 Feedback system Probable cause

Range of Check

The engine coolant temperature is approx. 80_C or more.

During stoichiometric feedback control

The vehicle is not being decelerated.

Set Conditions

Oxygen sensor (front) output voltage has been higher or lower than 0.5 V for

at least thirty seconds.

Malfunction of oxygen sensor (front)

Open or short circuit in the oxygen sensor (front)

circuit or loose connector contact Malfunction of engine-ECU <M/T>

Malfunction of engine-A/T-ECU <A/T>

Check the following connector:

C-46

Measure at oxygen sensor (front) connector C-46.

Disconnect the connector and

measure at the harness side. Resistance between terminal 2

and earth

OK:

2Wor less

Measure at oxygen sensor (front) connector C-46.

Measure the voltage at the

oxygen sensor (front) terminal Engine: 2,500 r/min (after

warming up)

(1) Voltage between terminal 2 and

earth

OK:

(2) Voltage between terminal 1 and

Measure at engine-ECU connector C-40 <M/T> or engine-A/T-ECU connector C-175 <A/T>.

Check the following connector:

C-40 <M/T>, C-175 <A/T>

Check the trouble symptoms.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

0.5 V or less

earth

OK:

0 V and 0.8 V alternate.

Measure the voltage at the engine-ECU terminal <M/T> or engine-A/T-ECU terminal <A/T>. Engine: 2,500 r/min (after warming up) Voltage between terminal 76 <M/T>, 71 <A/T> and earth

OK:

0 V and 0.8 V alternate.

(1) NG

(2) NG

Repair

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness wire between the oxygen sensor (front) and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the trouble symptoms.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness wire between the oxygen sensor (front) and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Check the oxygen sensor (front). (Refer to P.13A-89.)

Check the following connector:

C-40 <M/T>, C-175 <A/T>

Check the harness wire between the oxygen sensor (front) and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Check the following connector:

C-40 <M/T>, C-175 <A/T>

Check the harness wire between the oxygen sensor (front) and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Repair

Transient malfunction (Refer to GROUP 00 - Points to Note for Intermittent Malfunctions.)

Repair

Replace

Repair

Page 21

MPI <4G6> -

Troubleshooting

13A-21

Code No. P0130 Oxygen sensor (front) system <sensor 1>

Range of Check

Three minutes have been passed since the engine has been started.

The engine coolant temperature is approx. 80_C or more.

Engine speed is 1,200 r/min or more

Driving on a level surface at constant speed.

Set Conditions

The oxygen sensor (front) output voltage is 4.5 V or more when the sensor

output voltage is 0.2 V or less and a voltage of 5 V is applied to the oxygen sensor (front) inside the engine-ECU.

Range of Check

Engine speed is 2,800 r/min or less

During driving

During air/fuel ratio feedback control

Set Conditions

The oxygen sensor (front) output frequency is s ix or less per 10 seconds on

average.

Probable cause

Malfunction of oxygen sensor (front)

Open or short circuit in the oxygen sensor (front)

circuit or loose connector contact Malfunction of engine-ECU <M/T>

Malfunction of engine-A/T-ECU <A/T>

Page 22

13A-22

MPI <4G6> -

Troubleshooting

Check the following connector:

C-46

Measure at oxygen sensor (front) connector C-46.

Disconnect the connector and

measure at the harness side. Resistance between terminal 2

and earth

OK:

2Wor less

Measure at oxygen sensor (front) connector C-46.

Measure the voltage at the

oxygen sensor (front) terminal. Engine: 2,500 r/min (after

warming up)

(1) Voltage between terminal 2 and

earth

OK:

(2) Voltage between terminal 1 and

Measure at engine-ECU connector C-40 <M/T> or engine-A/T-ECU connector C-175 <A/T>.

Check the following connector:

C-40 <M/T>, C-175 <A/T>

Check the trouble symptoms.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

0.5 V or less

earth

OK:

0 V and 0.8 V alternate.

Measure the voltage at the engine-ECU terminal. Engine: 2,500 r/min (after warming up) Voltage between terminal 76 <M/T>, 71 <A/T> and earth

OK:

0 V and 0.8 V alternate.

(1) NG

(2) NG

Repair

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness wire between the oxygen sensor (front) and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the trouble symptoms.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness wire between the oxygen sensor (front) and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Check the oxygen sensor (front). (Refer to P.13A-89.)

Check the following connector:

C-40 <M/T>, C-175 <A/T>

Check the harness wire between the oxygen sensor (front) and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Check the following connector:

C-40 <M/T>, C-175 <A/T>

Check the harness wire between the oxygen sensor (front) and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Repair

Transient malfunction (Refer to GROUP 00 - Points to Note for Intermittent Malfunctions.)

Repair

Replace

Repair

Page 23

MPI <4G6> -

Troubleshooting

13A-23

Code No. P0135 Oxygen sensor heater (front) system <sensor 1>

Range of Check

The engine coolant temperature is approx. 20_C or more.

The oxygen sensor heater (front) remains on.

The engine speed is 50 r/min or more.

Battery voltage is 11 - 16 V.

Set Conditions

The current, which flows through the oxygen sensor heater (front), is 0.2 A

or less or 3.5 A or more for six seconds.

Measure at oxygen sensor (front) connector C-46.

Disconnect the connector and

measure at the harness side. Resistance between terminals 3

and 4

OK:

4.5 - 8.0

Check the following connector:

C-46

Measure at oxygen sensor (front) connector C-46.

Disconnect the connector and

measure at the harness side. Ignition switch: ON

Voltage between terminal 3 and

earth

OK:

System voltage

Measure at engine-ECU connector C-38 <M/T> or engine-A/T-ECU connector C-177 <A/T>.

Measure the voltage at the

engine-ECU terminal. Ignition switch: ON

Voltage between terminal 60

<M/T>, 3 <A/T> and earth

OK:

System voltage

Check the following connector:

C-38 <M/T>, C-177 <A/T>

Check the harness wires between the oxygen sensor (front) and the engine-ECU <M/T> or engine-A/T-ECU <A/T> and between the oxygen sensor (front) and the engine control relay.

Check the trouble symptoms.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Replace

Repair

Check the following connector:

C-31

Check the harness wires between the oxygen sensor (front) and the engine control relay, and repair if necessary.

Check the following connector:

C-38 <M/T>, C-177 <A/T>

Check the harness wire between the oxygen sensor (front) and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Repair

Transient malfunction (Refer to GROUP 00 - Points to Note for Intermittent Malfunctions.)

Probable cause

Malfunction of oxygen sensor heater (front)

Open or short circuit in the oxygen sensor heater

(front) circuit or loose connector contact Malfunction of engine-ECU <M/T>

Malfunction of engine-A/T-ECU <A/T>

Repair

Page 24

13A-24

MPI <4G6> -

Troubleshooting

Code No. P0136 Oxygen sensor (rear) system <sensor 2>

Range of Check

Three minutes have been passed since the engine has been started.

The engine coolant temperature is approx. 80_C or more.

Engine speed is 1,200 r/min or more

Driving on a level surface at constant speed.

Set Conditions

The oxygen sensor (rear) output voltage is 4.5 V or more when the sensor

output voltage is 0.2 V or less and a voltage of 5 V is applied to the oxygen sensor (rear) inside the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Probable cause

Malfunction of oxygen sensor (rear)

Open or short circuit in the oxygen sensor (rear)

circuit or loose connector contact Malfunction of engine-ECU <M/T>

Malfunction of engine-A/T-ECU <A/T>

Page 25

MPI <4G6> -

Troubleshooting

13A-25

Check the following connector:

C-85

Measure at oxygen sensor (rear) connector C-85.

Disconnect the connector and

measure at the harness side. Resistance between terminal 2

and earth

OK:

2Wor less

Measure at oxygen sensor (rear) connector C-85.

Measure the voltage at the

oxygen sensor (rear) terminal. Engine: 2,500 r/min (after

warming up)

(1) Voltage between terminal 2 and

earth

OK:

(2) Voltage between terminal 1 and

Measure at engine-ECU connector C-40 <M/T> or engine-A/T-ECU connector C-175 <A/T>.

Check the following connector:

C-40 <M/T>, C-175 <A/T>

Check the trouble symptoms.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

0.5 V or less

earth

OK:

0 V and 0.8 V alternate.

Measure the voltage at the engine-ECU terminal <M/T> or engine-A/T-ECU terminal <A/T>. Engine: 2,500 r/min (after warming up) Voltage between terminal 75 <M/T>, 73 <A/T> and earth

OK:

0 V and 0.8 V alternate.

(1) NG

(2) NG

Repair

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness wire between the oxygen sensor (rear) and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the trouble symptoms.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness wire between the oxygen sensor (rear) and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Check the oxygen sensor (rear). (Refer to P.13A-90.)

Check the following connectors:

C-40 <M/T>, C-175 <A/T>

Check the harness wire between the oxygen sensor (rear) and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Check the following connector:

C-40 <M/T>, C-175 <A/T>

Check the harness wire between the oxygen sensor (rear) and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Repair

Transient malfunction (Refer to GROUP 00 - Points to Note for Intermittent Malfunctions.)

Repair

Replace

Repair

Page 26

13A-26

MPI <4G6> -

Troubleshooting

Code No. P0141 Oxygen sensor heater (rear) system <sensor 2>

Range of Check

The engine coolant temperature is approx. 20_C or more.

The oxygen sensor heater (rear) remains on.

The engine speed is 50 r/min or more.

Battery voltage is 11 - 16 V.

Set Conditions

The current, which flows through the oxygen sensor heater (rear), is 0.2 A or

less or 3.5 A or more for six seconds.

Measure at oxygen sensor (rear) connector C-85.

Disconnect the connector and

measure at the harness side. Resistance between terminals 3

and 4

OK:

11 - 18

Check the following connector:

C-85

Measure at oxygen sensor (rear) connector C-85.

Disconnect the connector and

measure at the harness side. Ignition switch: ON

Voltage between terminal 3 and

earth

OK:

System voltage

Measure at engine-ECU connector C-38 <M/T> or engine-A/T-ECU connector C-177 <A/T>.

Measure the voltage at the

engine-ECU terminal <M/T> or engine-A/T-ECU terminal <A/T>. Ignition switch: ON

Voltage between terminal 54

<M/T>, 26 <A/T> and earth

OK:

System voltage

Check the following connector:

C-38 <M/T>, C-177 <A/T>

Check the harness wires between the oxygen sensor (rear) and the engine-ECU <M/T> or engine-A/T-ECU <A/T> and between the oxygen sensor (rear) and the engine control relay.

Check the trouble symptoms.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Replace

Repair

Check the following connector:

C-31

Check the harness wires between the oxygen sensor (rear) and the engine control relay, and repair if necessary.

Check the following connector:

C-38 <M/T>, C-177 <A/T>

Check the harness wire between the oxygen sensor (rear) and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Repair

Transient malfunction (Refer to GROUP 00 - Points to Note for Intermittent Malfunctions.)

Probable cause

Malfunction of oxygen sensor heater (rear)

Open or short circuit in the oxygen sensor heater

(rear) circuit or loose connector contact Malfunction of engine-ECU <M/T>

Malfunction of engine-A/T-ECU <A/T>

Repair

Page 27

MPI <4G6> -

Troubleshooting

Code No. P0170 Abnormal fuel system Probable cause

Range of Check

Engine: Being learning the air/fuel ratio

Set Conditions

Ten seconds or more have been passed while the fuel injection amount

compensation value is too low.

Ten seconds or more have been passed while the fuel injection amount

compensation value is too high.

Incorrect fuel pressure

Malfunction of fuel supply system

Malfunction of oxygen sensor (front)

Malfunction of intake air temperature sensor

Malfunction of barometric pressure sensor

Malfunction of air flow sensor

Malfunction of engine-ECU <M/T>

Malfunction of engine-A/T-ECU <A/T>

13A-27

MUT-IIData list

13 Intake air temperature sensor (Refer to P.13A-75.)

MUT-IIData list

21 Engine coolant temperature sensor (Refer to P.13A-75.)

MUT-IIData list

25 Barometric pressure sensor (Refer to P.13A-75.)

Check the injector (Refer to P.13A-93*.)

Check the following connectors:

C-34 <M/T>, C-177 <A/T>, B-02, B-03, B-05, B-36

Check the harness wire between the engine-ECU <M/T> or engine-A/T-ECU <A/T> and the injector connector.

Check the fuel pressure (Refer to P.13A-85*.)

MUT-IIData list

81 Long-term fuel compensation (Refer to P.13A-75.)

Is fuel trim more or less than zero?

Less than zero

MUT-IIData list

12 Volume air flow sensor (Refer to P.13A-75.)

Does the tester indi-

cate more than the standard value?

Yes

Replace the volume air flow sensor.

Check for fuel leaks

from injector. Check for entry of

foreign matter (water, kerosene,etc.) into the fuel.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

More than zero

Check the intake air temperaturesensor system.(Refer to P.13A-14, INSPECTION PROCEDURE FOR DIAGNOSTIC TROUBLE CODE P0110.)

Check the engine coolant temperature sensor system. (Refer to P.13A-16, INSPECTION PROCEDURE FOR DIAGNOSTIC TROUBLE CODE P0115.)

Check the barometric pressure sensor system. (Refer to P.13A-12, INSPECTION PROCEDURE FOR DIAGNOSTIC TROUBLE CODE P0105.)

Replace

Repair

Check if air was drawn into the intake system.

MUT-IIData list

12 Volume air flow sensor (Refer to P.13A-75.)

Does the tester indi-

cate less than the standard value?

Yes

Replace the volume air flow sensor.

Repair

Check for clogging of

the injector. Check for clogging of

the fuel filter and fuel line. Check the fuel pump

(insufficient discharge rate.) Check for exhaust

leaks (oxygen sensor installation section, cracks in exhaust manifold, cracks in front pipe, etc.). Check for entry of

foreign matter (water, kerosene,etc.) into the fuel.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

NOTE: *: Refer to the ’97 GALANT Workshop Manual (Pub. No. PWDE9611)

Page 28

13A-28

MPI <4G6> -

Troubleshooting

Code No. P0201 No. 1 injector system Code No. P0202 No. 2 injector system Code No. P0203 No. 3 injector system Code No. P0204 No. 4 injector system

Range of Check

Engine speed is approx. 50 - 1,000 r/min

The throttle position sensor output voltage is 1.15 V or less.

Actuator test by MUT-IIis not carried out.

Set Conditions

Surge voltage of injector coil is not detected for 4 seconds.

MUT-IIActuator Test

01 No. 1 injector 02 No. 2 injector 03 No. 3 injector 04 No. 4 injector

OK:

The idling condition should change

Check the following connectors:

B-02, B-03, B-05, B-36

Check the injector. (Refer to P.13A-93*.)

Measure at the injector connector B-02, B-03, B-05, B-36.

Disconnect the connector, and measure at the harness side.

Voltage between 1 and earth (Ignition switch: ON)

OK:

System voltage

Check the following connector:

Measure at the engine-ECU connector C-34 <M/T> or engine-A/TECU connector C-177<A/T>.

Disconnect the connector, and measure at the harness side.

Voltage between 1, 2, 14, 15 and earth (Ignition switch: ON)

<M/T> Voltagebetween 1,2, 9,24 and earth (Ignition switch: ON)<A/T>

OK:

System voltage

Check trouble symptoms.

Use an analyzer to measure the signal waveform at injector connector B-02, B-03, B-05, B-36.

Use a test harness (MB991348) to connect the connector, and

measure at the pick-up harness side. Engine: Idling

The voltage between terminal 2 and earth

OK:

A normal waveform should be displayed as described on P.13A-88 (INSPECTION PROCEDURE USING AN ANALYZER).

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

C-34 <M/T>, C-177 <A/T>

Probable cause

Malfunction of the injector

Improper connector contact, open circuit or short-cir-

cuited harness wire of the injector circuit Malfunction of engine-ECU <M/T>

Malfunction of engine-A/T-ECU <A/T>

Intermittent malfunction (Refer to GROUP 00 - Points to Note for Intermittent Malfunctions.)

Repair

Replace

Check the harness wire between the engine control relay and the injector connector, and repair if necessary.

Repair

Check the harness wire between the engine-ECU <M/T> or engine-A/T-ECU <A/T> and the injector connector, and repair if necessary.

Intermittent malfunction (Refer to GROUP 00 - Points to Note for Intermittent Malfunctions.)

NOTE: *: Refer to the ’97 GALANT Workshop Manual (Pub. No. PWDE9611)

Page 29

MPI <4G6> -

Troubleshooting

Code No. P0300 Ignition coil (power transistor) system Probable cause

Range of Check

Engine speed is approx. 50 - 4,000 r/min.

Engine is not cranking.

Set Conditions

The ignition failure sensor does not send a signal about a certain cylinder for

four seconds.

Malfunction of the ignition coil

Malfunction of the ignition failure sensor

Malfunction of spark plug

Open or short circuit in the primary ignition circuit

or loose connector contact Malfunction of engine-ECU <M/T>

Malfunction of engine-A/T-ECU <A/T>

13A-29

Page 30

13A-30

MPI <4G6> -

Troubleshooting

MUT-IIActuator Test

01 No. 1 injector 02 No. 2 injector 03 No. 3 injector 04 No. 4 injector

OK:

The idling condition should

Reference When the cylinder (defective cylinder) where idling condition does not change is detected after suspending the injector, go to (1) and inspect the spark plug, the ignition coil, the connector, and the harness of the defective cylinder. (When more than one cylinder are detected, inspect all of them.) When all the cylinders are OK, go to (2).

change.

(2)

(1)

Check the following connectors:

The ignition coil connectors for a defective cylinder (B-01, B-11).

Check the spark plug and the ignition coil for a defective cylinder. (Refer to GROUP 16 - Ignition System.)

Check the following connector:

C-34 <M/T>, C-177 <A/T>

Check the harness wire between the engine-ECU <M/T> or engine-A/T-ECU <A/T> and the ignition coil connector for defective cylinder.

Use an analyzer to measure the signal waveform at engine-ECU connector C-34 <M/T> or engine-A/T-ECU connector C-177 <A/T>.

Engine: Idling

The voltage between the ignition coil primary signal terminal for a defective cylinder

and earth

OK:

A normal waveform should be displayed as described on P.13A-88* (Inspection Procedure Using an Analyzer).

Repair the ignition coil assembly for a defective cylinder and the spark plug.

Repair

Replace

Repair

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Use an analyzer to measure the signal waveform at the ignition failure sensor connector B-105.

Use test harness (MB991536) to

connect the connector, and measure at the pick-up harness. Engine: Idling

The voltage between terminal 2

and earth

OK:

A normal waveform should be displayed as described on P.13A-88* (INSPECTION PROCEDURE USING AN

Reference When a normal waveform is displayed, compare it with that of the ignition coil primary signal at the engine-ECU terminal <M/T> or engine-A/T-ECU <A/T> to determine the cylinder (defective cylinder) with an abnormal waveform.

abnormal, go to (1)

abnormal, go to (3)

displayed, go to (4).

ANALYZER).

When one or more cylinders are

When all of the cylinders are

When a normal waveform is

(1)

(3)

(4)

Check the following connectors:

C-38 <M/T>, C-176 <A/T>, B-105

Check the harness wires between the ignition failure sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and between the ignition failure sensor and earth.

Repair the ignition failure sensor.

Check the trouble symptoms.

Check the spark plug and the ignition coil for a defective cylinder. (Refer to GROUP 16 - Ignition System.)

Repair

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Intermittent malfunction (Refer to GROUP 00 - Points to Note for Intermittent Malfunctions.)

Page 31

MPI <4G6> -

Troubleshooting

13A-31

Code No. P0301 No. 1 cylinder misfire detected Code No. P0302 No. 2 cylinder misfire detected Code No. P0303 No. 3 cylinder misfire detected Code No. P0304 No. 4 cylinder misfire detected

Range of Check

The engine speed is 500 - 4,500 r/min.

While the engine is running except deceleration and sudden acceleration.

Set Conditions

The number of misfires exceeds a predetermined number per 200 engine

revolutions (Misfire has occurred in only one cylinder).

The number of misfires exceeds a predetermined number per 100 engine

revolutions (Misfire has occurred in only one cylinder).

Check the following connectors:

B-01, B-11

Measure at ignition coil connectors B-01, B-11.

Disconnect the connector and

measure at the harness side.

(1) The voltage between terminal 1

and earth (Ignition switch: ON)

OK:

(2) The voltage between terminal 3

(3) The resistance between terminal

Check the ignition coil (Refer to GROUP 16 - Ignition System.)

System voltage

and earth (Engine: Cranking)

OK:

0.5 - 4.0 V

2 and earth

OK:

2Wor less

(1) NG

(2) NG

(3) NG

Repair

Check the following connectors:

B-105, C-92, C-105, C-131

Check the ignition failure sensor (Refer to GROUP 16 - Ignition System.)

Check the harness wire between the ignition coil and the ignition failure sensor, and between the ignition switch and the ignition failure sensor.

Check the following connector:

C-34 <M/T>, C-177 <A/T>

Check the harness wire between the ignition coil and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the trouble symptoms.

Check the harness wire between the ignition coil and the earth, and repair if necessary.

Probable cause

Malfunction of the ignition system

Abnormal compression

Malfunction of injector

Malfunction of engine-ECU <M/T>

Malfunction of engine-A/T-ECU <A/T>

Repair

Replace

Repair

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the spark plugs.

Check the compression pressure. (Refer to GROUP 11A - On-vehicle Service.)

Check the trouble symptoms.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Replace

Repair

Page 32

13A-32

MPI <4G6> -

Troubleshooting

Code No. P0325 Detonation sensor system Probable cause

Range of Check

Engine: Two seconds after the engine has been started

Set Conditions

Changes in sensor output voltage (detonation sensor peak voltage per 1/2

crankshaft rotation) in 200 consecutive cycles are 0.06 V or less.

Malfunction of the detonation sensor

Open or short circuit in the detonation sensor

circuit or loose connector contact Malfunction of engine-ECU <M/T>

Malfunction of engine-A/T-ECU <A/T>

Check the following connector:

Measure at the detonation sensor connector B-34.

Disconnect the connector and measure at the harness

side. The resistance between terminal 2 and earth

OK:

2Wor less

Check the following connector:

Check the harness wire between the detonation sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the trouble symptoms.

Replace the detonation sensor.

Check the trouble symptoms.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

B-34

C-40 <M/T>, C-175 <A/T>

Repair

Check the harness wire between the detonation sensor and earth, and repair if necessary.

Repair

Intermittent malfunction (Refer to GROUP 00 - Points to Note for Intermittent Malfunctions.)

Code No. P0335 Crank angle sensor system Probable cause

Range of Check

Engine is cranking

Set Conditions

Sensor output voltage does not change for 4 seconds (no pulse signal input).

Malfunction of the crank angle sensor.

Open or short circuit in the crank angle sensor

circuit or loose connector contact. Malfunction of engine-ECU <M/T>

Malfunction of engine-A/T-ECU <A/T>

Page 33

MPI <4G6> -

Troubleshooting

13A-33

MUT-IIData list

22 Crank angle sensor

OK:

Refer to P.13A-75, DATA LIST REFERENCE TABLE.

Check the following connector:

B-77

Measure at the crank angle sensor connector B-77.

Disconnect the connector and

measure at the harness side.

(1) The resistance between terminal

1 and earth

OK:

(2) The voltage between terminal 2

(3) The voltage between terminal 3

2Wor less

and earth (Ignition switch: ON)

OK:

4.8 - 5.2 V

and earth (Ignition switch: ON)

OK:

System voltage

(1) NG

(2) NG

(3) NG

Intermittent malfunction (Refer to GROUP 00 - Points to Note for Intermittent Malfunctions.)

Repair

Check the harness between the crank angle sensor and earth, and repair if necessary.

Measure at engine-ECU connector C-40 <M/T> or engine-A/T-ECU connector C-176 <A/T>.

Measure the voltage at the

engine-ECU terminal <M/T> or engine-A/T-ECU terminal <A/T>. Disconnect the connector B-77

Ignition switch: ON

The voltage between terminal 89

<M/T>, 45 <A/T> and earth

OK:

4.8 - 5.2 V

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness wire between the crank angle sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the trouble symptoms.

Check the following connector:

C-31

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness wire between the crank angle sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Repair

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Repair

Use an analyzer to measure the output waveform at the crank angle sensor connector B-77.

Use the test harness (MB991658)

to connect the connector, and measure at the pick-up harness side. Engine: Idling

The voltage between terminal 3

and earth

OK:

A normal waveform should be displayed as described on P.13A-88 (Inspection Procedure Using an Analyzer). Its maximum value should be 4.8 V or more, and its minimum value should be 0.6 V or less

with no noise in waveform.

Check the trouble symptoms.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the harness wire between the crank angle sensor and the engine control relay, and repair if necessary.

Check the crank angle sensor vane.

Replace the crank angle sensor.

Check the trouble symptoms.

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness wires between the crank angle sensor and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, crank angle sensor and the engine control relay, and the crank angle sensor and earth. Then, repair if necessary.

Replace

Repair

Page 34

13A-34

MPI <4G6> -

Troubleshooting

Code No. P0340 Camshaft position sensor system Probable cause

Range of Check

Ignition switch: ON

Engine speed: 50 r/min or more

Set Conditions

The sensor output voltage does not change for 4 seconds (no pulse signal

input).

Malfunction of the camshaft position sensor

Open or short circuit in the camshaft position

sensor circuit or loose connector contact. Malfunction of engine-ECU <M/T>

Malfunction of engine-A/T-ECU <A/T>

Page 35

MPI <4G6> -

Troubleshooting

13A-35

Check the following connector:

B-64

Measure at camshaft position sensor connector B-64.

Disconnect the connector and

measure at the harness side.

(1) The voltage between terminal 3

and earth (Ignition switch: ON)

OK:

(2) The voltage between terminal 2

(3) The resistance between terminal

Use an analyzer to measure the output waveform at camshaft position sensor connector B-64.

D D

Check the trouble symptoms.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

System voltage

and earth (Ignition switch: ON)

OK:

4.8 - 5.2 V

1 and earth

OK:

2Wor less

Use test harness (MB991709) to connect the connector, and measure at the pick-up harness. Engine: Idling The voltage between terminal 2 and earth

OK:

A normal waveform should be displayed as described on P.13A-88 (Inspection Procedure Using an Analyzer), its maximum value should be 4.8 V or more, and its minimum value should be 0.6 V or less

with no noise in waveform

(1) NG

(2) NG

(3) NG

Repair

Check the following connector:

C-31

Check the harness wire between the camshaft position sensor connector and the engine control relay, and repair if necessary.

Measure at engine-ECU connector C-40 <M/T> or engine-A/T-ECU connector C-176 <A/T>.

Measure the voltage at the

engine-ECU terminal <M/T> or engine-A/T-ECU terminal <A/T>. Disconnect connector B-64.

Ignition switch: ON

The voltage between terminal 88

<M/T>, 56 <A/T> and earth

OK:

4.8 - 5.2 V NG

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness wire between the intermediate connector and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the trouble symptoms.

Check the harness wire between the camshaft position sensor connector and earth, and repair if necessary.

Check the camshaft position sensing cylinder.

Replace the camshaft position sensor.

Check the trouble symptoms.

Check the following connectors:

B-64, C-31, C-40, C-176

Check the harness wires between the camshaft position sensor connector and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, the camshaft position sensor connector and the engine control relay, and the camshaft position sensor connector and earth. Then, repair if necessary.

Intermittent malfunction (Refer to GROUP 00 - Points to Note for Intermittent Malfunctions.)

Repair

Check the following connector:

C-40 <M/T>, C-176 <A/T>

Check the harness wire between the camshaft position sensor connector and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Repair

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Replace

Repair

Page 36

13A-36

MPI <4G6> -

Troubleshooting

Code No. P0403 EGR control solenoid valve system Probable cause

Range of Check

Ignition switch: ON

Battery voltage is 10 V or more.

Set Conditions

The solenoid coil surge voltage (battery voltage + 2 V) is not detected when

the purge control solenoid valve is turned from on to off.

Malfunction of the EGR control solenoid valve

Open or short circuit in the EGR control solenoid

valve circuit or loose connector contact Malfunction of engine-ECU <M/T>

Malfunction of engine-A/T-ECU <A/T>

MUT-IIActuator Test

10 EGR control solenoid valve

OK:

Operating sound can be heard and the valve vibrates.

Measure at the EGR control solenoid valve connector B-06.

Disconnect the connector, and

measure at the solenoid valve side. The resistance between terminals

1 and 2

OK:

28 - 36W(at 20_C)

Check the following connector:

B-06

Measure at the EGR control solenoid valve connector B-06.

Disconnect the connector and

measure at the harness side. Ignition switch: ON

The voltage between terminal 1

and earth

OK:

System voltage

Measure at engine-ECU connector C-34 <M/T> or engine-A/T-ECU connector C-177 <A/T>.

Measure the voltage at the

engine-ECU terminal <M/T> or engine-A/T-ECU terminal <A/T>. Ignition switch: ON

The voltage between terminal 6

and earth

OK:

System voltage

Check the following connector:

C-34 <M/T>, C-177 <A/T>

Check the harness wires between the EGR control solenoid valve and the engine control relay, and between the EGR control solenoid valve and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the trouble symptoms.

Intermittent malfunction (Refer to GROUP 00 - Points to Note for Intermittent Malfunctions.)

Replace

Repair

Check the following connector:

C-31

Check the harness wire between the EGR control solenoid valve and the engine control relay, and repair if necessary.

Check the following connector:

C-34 <M/T>, C-177 <A/T>

Check the harness wire between the EGR control solenoid valve and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Repair

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Page 37

MPI <4G6> -

Troubleshooting

Code No. P0420 Catalyst malfunction Probable cause

Range of Check

The engine speed is 3,000 r/min or less.

During driving

During air/fuel ratio feedback control

Set Conditions

The ratio between the oxygen sensor (rear) and the oxygen sensor (front)

output frequencies reaches 0.8 per 12 seconds on average.

Malfunction of catalyst

Malfunction of the oxygen sensor (front)

Malfunction of the oxygen sensor (rear)

Malfunction of engine-ECU <M/T>

Malfunction of engine-A/T-ECU <A/T>

13A-37

Check the exhaust manifold. (Are there any cracks?)

MUT-IIData list

59 Oxygen sensor (rear)

Transmission: 2nd gear <M/T>, L range <A/T>

Drive with wide open throttle

OK:

600 - 1,000 mV

MUT-IIData list

11 Oxygen sensor (front)

OK:

600 - 1,000 mV when racing suddenly

MUT-IIData list

11 Oxygen sensor (front)

Transmission: 2nd gear <M/T>, L range <A/T>

OK:

Changeover between 0 - 400 mV and 600 - 1,000 mV occur 15 times in 10 seconds.

Replace the oxygen sensor (rear).

Check the trouble symptoms.

Replace the catalytic converter.

Repair

Check the oxygen sensor (rear) system <sensor 2> (Refer to P.13A-24, INSPECTION PROCEDURE FOR DIAGNOSTIC TROUBLE CODE P0136.)

Check the oxygen sensor (front) system <sensor 1> (Refer to P.13A-21, INSPECTION PROCEDURE FOR DIAGNOSTIC TROUBLE CODE P0130.)

Replace the oxygen sensor (front).

Check the trouble symptoms.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Page 38

13A-38

MPI <4G6> -

Troubleshooting

Code No. P0443 Purge control solenoid valve system Probable cause

Range of Check

Ignition switch: ON

Battery voltage is 10 V or more.

Set Conditions

The solenoid coil surge voltage (battery voltage + 2 V) is not detected when

the purge control solenoid valve is turned from on to off.

Malfunction of the purge control solenoid valve

Open or short circuit in the purge control solenoid

valve circuit or loose connector contact Malfunction of engine-ECU <M/T>

Malfunction of engine-A/T-ECU <A/T>

MUT-IIActuator Test

08 Purge control solenoid valve

OK:

Operating sound can be heard and the valve vibrates.

Measure at the purge control solenoid valve connector B-04.

Disconnect the connector, and

measure at the solenoid valve side. The resistance between terminals

1 and 2

OK:

28 - 36W(at 20_C)

Check the following connector:

B-04

Measure at the purge control solenoid valve connector B-04.

Disconnect the connector and

measure at the harness side. Ignition switch: ON

The voltage between terminal 2

and earth

OK:

System voltage

Measure at engine-ECU connector C-34 <M/T> or engine-A/T-ECU connector C-177 <A/T>.

Measure the voltage at the

engine-ECU terminal <M/T> or engine-A/T-ECU terminal <A/T>. Ignition switch: ON

The voltage between terminal 9

<M/T>, 34 <A/T> and earth

OK:

System voltage

Check the following connector:

C-34 <M/T>, C-177 <A/T>

Check the harness wires between the purge control solenoid valve and the engine control relay, and between the purge control solenoid valve and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Intermittent malfunction (Refer to GROUP 00 - Points to Note for Intermittent Malfunctions.)

Replace

Repair

Check the following connector:

C-31

Check the harness wire between the purge control solenoid valve and the engine control relay, and repair if necessary.

Check the following connector:

C-34 <M/T>, C-177 <A/T>

Check the harness wire between the purge control solenoid valve and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Repair

Check the trouble symptoms.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Page 39

MPI <4G6> -

Troubleshooting

Code No. P0500 Vehicle speed sensor system Probable cause

Range of Check

Engine: Two seconds after the engine was started

Idle switch: OFF

Engine speed: 2,500 r/min or more

During high engine load

Set Conditions

The sensor output voltage does not change for 2 seconds (no pulse signal

input).

Malfunction of the vehicle speed sensor

Open or short circuit in the vehicle speed sensor

circuit or loose connector contact Malfunction of engine-ECU <M/T>

Malfunction of engine-A/C-ECU <A/T>

13A-39

Does the speedometer operate normally?

Yes

Use an analyzer to measure the output waveform of the vehicle speed sensor at engine-ECU connector C-40 <M/T> or engine-A/T-ECU connector C-175 <A/T>.

Driving the vehicle

The voltage between terminal 86 <M/T>, 80 <A/T> and

earth

OK:

A normal waveform should be displayed as described in OSCILLOSCOPE INSPECTION PROCEDURE, and noise should not be displayed in the waveform. (Refer to GROUP 23 - Troubleshooting.)

Check the following connector:

Check the trouble symptoms.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

C-40 <M/T>, C-175 <A/T>

Check the vehicle speed sensor (Refer to GROUP 54 - Combination Meter.)

Check the following connectors:

B-65, B-66, C-40 <M/T>, B-67, C-175 <A/T>, C-47 <LHD>, C-49 <RHD>

Check the harness wire between vehicle speed sensor connector and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Repair

Code No. P0505 Idle speed control (ISC) system Probable cause

Check Area

Vehicle speed has reached 1.5 km/h at least once.

Under the closed loop idle speed control.

Judgment Criteria

Actual idle speed has continued to be higher than the target idle speed by

300 r/min or more for 10 sec.

Check Area

Vehicle speed has reached 1.5 km/h at least once.

During idle speed closed loop control.

The highest temperature at the last drive is 45_C or less.

Engine coolant temperature is approx. 80_C or more.

Battery voltage is 10 V or more.

Barometric pressure is 76 kPa or higher.

Intake air temperature is - 10_C or more.

Judgment Criteria

Actual idle speed has been minimum 200 r/min higher than the target idle

speed for ten seconds.

Check Area

During idle speed closed loop control.

Engine coolant temperature is about 80_C or higher.

Battery voltage is 10 V or higher.

Power steering switch is off.

Volumetric efficiency is 40 % or lower.

Barometric pressure is 76 kPa or higher.

Intake air temperature is - 10_C or more.

Judgment Criteria

Actual idle speed has been minimum 100 r/min higher than the target idle

speed for ten seconds.

Malfunction of idle speed control (ISC) servo

Improper connector contact, open circuit or

short-circuit harness wire Malfunction of engine-ECU <M/T>

Malfunction of engine-A/C-ECU <A/T>

Repair

Page 40

13A-40

MPI <4G6> -

Troubleshooting

MUT-IISelf-Diag code

Is any diagnosis code other than No. P0505 output?

Check intake air hose and intake manifold for air intake.

Check the throttle body (around the throttle valve) for contamination.

Check the idle speed control (ISC) servo. (Refer to P.13C-95*.)

Check the following connector:

B-10

Measure at the idle control servo connector B-10.

Disconnect the connector, and

measure at the harness side. Ignition switch: ON

The voltage between terminal 2

and earth The voltage between terminal 5

and earth

OK:

System voltage

Measureat engine-ECU connectorC-34 <M/T> or engine-A/T-ECU connector C-177 <A/T>.

Use test harness (MB991709) to

connecttheconnector,andmeasure at the pick-up harness side. The voltage between terminal 4

<M/T> or 14 <A/T> and earth The voltage between terminal 5

<M/T> or 15 <A/T> and earth The voltage between terminal 17

<M/T> or 28 <A/T> and earth The voltage between terminal 18

<M/T> or 29 <A/T> and earth

OK:

The voltage changes as follows for three seconds when the ignition switch is turned ON. (When using a circuit tester) 5 V and 8 V alternates (When using an analyzer) 1 V or lessand system voltage alternates

To the next page

Yes

RefertoP.13A-8, INSPECTIONCHART FOR DIAGNOSIS CODES.

Repair

Clean around the throttle valve. (Refer to P.13C-81*.)

Replace

Repair

Check the following connectors:

C-49 <LHD>, C-31

Check the harness wire between the engine control relay and the idle speed control servo, and repair if necessary.

Check the following connector:

C-34 <M/T>, C-177 <A/T>

Check the harness wire between the idle speed control servo and the engineECU <M/T> or engine-A/T-ECU <A/T>.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Repair

NOTE: *: Refer to the ’97 GALANT Workshop Manual (Pub. No. PWDE9611)

Page 41

MPI <4G6> -

From the previous page

Check the following connector:

C-34 <M/T>, C-177 <A/T>

Check the harness wires between the engine control relay and the idle speed control servo, and between the idle speed control servo and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check trouble symptoms.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

MPI <4G6> -

Repair

Intermittent malfunction (Refer to GROUP 00 - Points to Note for Intermittent Malfunctions.)

Troubleshooting

Code No. P0510 Idle Position Switch System Probable cause

Check Area

Throttle position sensor output voltage is 2.0 V or more.

Judgment Criteria

Idle position switch has been turned on.

Check Area

Repeat the *1 drive and *2 stop 15 times or more.

*1 drive: The vehicle remains under the following conditions for at least two

seconds; engine speed is 1,500 rpm or higher, air flow sensor output waveform is 100 Hz or higher, and vehicle speed is more than 30 km/h for two seconds.

*2 stop: The vehicle remains under the following conditions for at least two

seconds; engine speed is 800 rpm or lower, and vehicle speed is less than

1.5 km/h.

Judgment Criteria

Idle position switch remains off.

Malfunction of idle position switch

Open or shorted idle position switch circuit, or

loose connector. Malfunction of engine-ECU <M/T>

Malfunction of engine-A/T-ECU <A/T>

13A-41

MUT-IIData list

26 Idle position switch (Refer to P.13A-75, DATA LIST REFERENCE TABLE.)

Check the idle position switch. (Refer to P.13A-91*.)

Check the following connector:

Measure at the throttle position sensor connector B-07.

Disconnect the connector, and measure at the harness

side. Voltage between 3 and ground (Ignition switch: ON)

OK:

4 V or higher

Continuity between 4 and ground

OK:

Continuity

Check the following connector:

Check trouble symptom.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

B-07

Repair

Transient malfunction (Refer to GROUP 00 - Points to Note for Intermittent Malfunctions.)

Replace the throttle position sensor (TPS).

Repair

Check the following connectors:

Check trouble symptom.

Check the harness wire between engine-ECU <M/T> or engine-A/T-ECU <A/T> and throttle position sensor connector.

Replace the engine-ECU <M/T> or engine-A/TECU <A/T>.

C-40

Repair

NOTE: *: Refer to the ’97 GALANT Workshop Manual (Pub. No. PWDE9611)

Page 42

13A-42

MPI <4G6> -

Troubleshooting

Code No. P0551 Power steering fluid pressure switch system

Check Area

Intake air temperature is - 10_C or higher.

Barometric pressure is 76 kPa or higher.

Engine coolant temperature is 30_C or more.

Repeat the *1 drive and *2 stop ten times or more.

*1: Engine speed is 2,500 r/min or higher, volumetric efficiency is 55 % or higher

and vehicle speed is 5 km/h or higher for 4 seconds or more. *2: Vehicle speed is 1.5 km/h or lower. Judgment Criteria

Power steering pressure switch remains on.

MUT-IIData list

27 Power steering fluid pressure switch (Refer to P.13A-75, DATA LIST REFERENCE TABLE.)

Check the power steering pressure switch. (Refer to GROUP 37A - On-vehicle Service.)

Check the following connector:

Measure at the power steering pressure switch connector B-76.

Disconnect the connector and measure at the harness

side. Voltage between 1 and ground (Ignition switch: ON)

OK:

Battery positive voltage

Check the following connector:

Check trouble symptom.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

B-76

Repair

Transient malfunction (Refer to GROUP 00 - Points to Note for Intermittent Malfunctions.)

Replace

Repair

Check the following connector:

C-176 <A/T>

Check trouble symptom.

Check the harness wire between engine-ECU <M/T> or engine-ATECU <A/T> and power steering pressure switch connector.

Replace the engine-ECU <M/T> or engine-ATECU <A/T>.

Probable cause

Power steering fluid pressure switch failed.

Open or shorted power steering fluid pressure

switch circuit or loose connector Malfunction of the engine-ECU <M/T>

Malfunction of the engine-A/C-ECU <A/T>

C-36 <M/T>,

Repair

Page 43

MPI <4G6> -

Troubleshooting

Code No. P1500 Alternator FR terminal system Probable cause

Range of Check

Engine speed: 50 r/min or more

Set Conditions

Input voltage from the alternator FR terminal is system voltage for 20

seconds.

Open circuit in alternator FR terminal circuit

Malfunction of engine-ECU <M/T>

Malfunction of engine-A/T-ECU <A/T>

13A-43

Check the following connector:

B-38

Measure at alternator connector B-38.

Use test harness (MB991519) to

connect the connector, and measure at the pick-up harness. Ignition switch: ON

The voltage between terminal 4

and earth

OK:

9 - 10 V

Measure at alternator connector B-38.

Use test harness (MB991519) to

connect the connector, and measure at the pick-up harness. Engine: Idling (After warming up)

Radiator fan: Not operating

The voltage between terminal 4

and earth

OK:

The voltage drops when the headlamps are turned on.

Repair

Measure at engine-ECU connector C-36 <M/T> or engine-A/T-ECU connector C-176 <A/T>.

Measure the voltage at the

engine-ECU terminal <M/T> or engine-A/T-ECU terminal <A/T>. Ignition switch: ON

The voltage between terminal 52

<M/T>, 54 <A/T> and earth

OK:

9 - 10 V

Check the following connector:

C-36 <M/T>, C-176 <A/T>

Check the harness wire between the intermediate connector and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the trouble symptoms.

Check the following connectors:

C-36 <M/T>, C-176 <A/T>, B-31

Check the harness wire between the alternator connector and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the trouble symptoms.

Replace the alternator.

Check the following connectors:

C-36 <M/T>, C-176 <A/T>, B-31

Check the harness wire between the intermediate connector and the engine-ECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Repair

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Replace

Repair

Check the trouble symptoms.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Intermittent malfunction (Refer to GROUP 00 - Points to Note for Intermittent Malfunctions.)

Page 44

13A-44

MPI <4G6> -

Troubleshooting

Cord No. P1610 Immobilizer system Probable cause

Range of Check

Ignition switch: ON

Set Conditions

Improper communication between the engine-ECU <M/T> or engine-A/T-ECU

<A/T> and the immobilizer-ECU

Open or short circuit, or loose connector contact

Malfunction of the immobilizer-ECU

Malfunction of the engine-ECU <M/T>

Malfunction of the engine-A/T-ECU <A/T>

NOTE (1) If the registered ignition keys are close each other when starting the engine, radio interference may

cause this code to be displayed.

(2) This code may be displayed when registering the key ID code.

Check the following connectors:

C-38 <M/T>, C-174 <A/T>, C-81, C-173

Check the harness wire between the immobilizer-ECU and the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the trouble symptoms.

Replace the immobilizer-ECU.

Repair

Replace

Check the trouble symptoms.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Page 45

MPI <4G6> -

Troubleshooting

INSPECTION CHART FOR TROUBLE SYMPTOMS

13A-45

Trouble symptom Inspection

procedure No.

Communication Communication with all systems is not possible. 1 13A-46 with MUT-IIis impossible.

Engine warning lamp and related parts

Starting No initial combustion (starting impossible) 5 13A-48

Idling stability Unstable idling (Rough idling, hunting) 8 13A-51 (Improper idling)

Idling stability When the engine is cold, it stalls at idling. (Die out) 11 13A-55 (Engine stalls)

Communication with engine-ECU <M/T> or engine-A/T-ECU <A/T> only is not possible.

The engine warning lamp does not illuminate right after the ignition switch is turned to the ON position.

The engine warning lamp remains illuminating and never goes out. 4 13A-47

Initial combustion but no complete combustion (starting impossible)

Long time to start (improper starting) 7 13A-50

Idling speed is high. (Improper idling speed) 9 13A-53

Idling speed is low. (Improper idling speed) 10 13A-54

When the engine becomes hot, it stalls at idling. (Die out) 12 13A-56

2 13A-46

3 13A-47

6 13A-49

Reference page

The engine stalls when starting the car. (Pass out) 13 13A-58

The engine stalls when decelerating. 14 13A-58

Driving Hesitation, sag or stumble 15 13A-59

The feeling of impact or vibration when accelerating 16 13A-60

The feeling of impact or vibration when decelerating 17 13A-60

Poor acceleration 18 13A-61

Surge 19 13A-63

Knocking 20 13A-64

Dieseling 21 13A-64

Too high CO and HC concentration when idling 22 13A-65

Low alternator output voltage (approx. 12.3 V) 23 13A-66

Idling speed is improper when A/C is operating 24 13A-66

Fans (radiator fan, A/C condenser fan) are inoperative 25 13A-67

Page 46

13A-46

MPI <4G6> -

Troubleshooting

INSPECTION PROCEDURE FOR TROUBLE SYMPTOMS

INSPECTION PROCEDURE 1

Communication with MUT-IIis not possible. (Communication with all systems is not possible.)

The cause is probably a defect in the power supply system (including earth) for the diagnosis line.

Measure at the diagnostic connector (16-pin) C-20.

Voltage between 16 and earth

OK:

Battery voltage

Measure at the diagnostic connector (16-pin) C-20.

Continuity between 4 and earth

Continuity between 5 and earth

OK:

Continuity

Replace the MUT-II.

Check the following connectors:

LHD: C-14, C-62, C-66 RHD: C-63, C-66, C-132, C-141

Check trouble symptom.

Check the harness wire between the diagnosticconnector (16-pin) and earth, and repair if necessary.

INSPECTION PROCEDURE 2

MUT-IIcommunication with engine-ECU <M/T> or engine-A/T-ECU <A/T> is impossible.

One of the following causes may be suspected.

No power supply to engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Defective earth circuit of engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Defective engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Improper communication line between engine-ECU <M/T> or engine-A/T-ECU

<A/T> and MUT-

Probable cause

Malfunction of the connector

Malfunction of the harness wire

Repair

Check the harness wire between the power supply and diagnostic connector (16-pin), and repair if necessary.

Probable cause

Malfunction of engine-ECU <M/T> or engine-A/T-ECU

<A/T> power supply circuit Malfunction of engine-ECU <M/T> or engine-A/T-ECU

<A/T> Open circuit between the engine-ECU <M/T> or

engine-A/T-ECU <A/T> and diagnosis connector

Check the following connectors:

C-38 <M/T>, C-175 <A/T>, C-49, C-66, C-83

Check trouble symptom.

Check the harness wire between engine-ECU <M/T> or engineA/T-ECU <A/T> and diagnosis connector.

Check the engine-ECU <M/T> or engine-A/T-ECU <A/T> power supply and earth circuit system. (Refer to P.13A-68, INSPECTION PROCEDURE 26.)

Repair

Page 47

INSPECTION PROCEDURE 3

MPI <4G6> -

Troubleshooting

13A-47

The engine warning lamp does not illuminate right after the ignition switch is turned to the ON position.

Because there is a burnt-out bulb, the engine-ECU <M/T> or engine-A/T-ECU <A/T> causes the engine warning lamp to illuminate for five seconds immediately after the ignitionswitchisturnedtoON.Iftheenginewarninglampdoesnotilluminateimmediately after the ignition switch is turned to ON, one of the malfunctions listed at right has probably occurred.

MUT-IIData list

16 engine-ECU power supply voltage (Refer to P.13A-75.)

Measure at the engine-ECU connector C-36 <M/T> or the engine-A/T-ECU connector C-117 <A/T>.

Disconnect the connector, and measure at the harness side.

Earth the terminal No. 36 <M/T> or No. 22 <A/T>.

OK:

The engine warning lamp illuminates.

Check a burnt-out bulb.

Measure at the combination meter connector D-03.

Disconnect the connector, and measure at the harness side.

Voltage between 4 and earth (Ignition switch: ON)

OK:

System voltage

Check the following connectors:

C-36 <M/T>, C-177 <A/T>, C-90, D-03

Check trouble symptom.

Replace

Check the engine-ECU <M/T> or engine-A/T-ECU <A/T> power supply and earth circuit. (Refer to P.13A-68, INSPECTION PROCEDURE 26.)

Check the following connector:

C-177 <A/T>

Check trouble symptom.

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Check the engine warning lamp power supply circuit, and repair if necessary.

Repair

Check the harness wire between combination meter and engineECU <M/T> or engine-A/T-ECU <A/T>, and repair if necessary.

Probable cause

Burnt-out bulb

Defective warning lamp circuit

Malfunction of the engine-ECU <M/T> or

engine-A/T-ECU <A/T>

C-36 <M/T>,

Repair

INSPECTION PROCEDURE 4

The engine warning lamp remains illuminating and never goes out.

In cases such as the above, the cause is probably that the engine-ECU <M/T> or engine-A/T-ECU <A/T> is detecting a problem in a sensor or actuator, or that one of the malfunctions listed at right has occurred.

MUT-IISelf-Diag code

Are diagnosis codes displayed?

Measure at the combination meter connector D-03.

Disconnect the connector, and measure at the harness side.

Disconnect the engine-ECU <M/T> or engine-A/T-ECU <A/T>

connector Continuity between 16 and earth

OK:

No continuity

Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

Yes

Probable cause

Short-circuit between the engine warning lamp and

engine-ECU <M/T> or engine-A/T-ECU <A/T> Malfunction of the engine-ECU <M/T> or

engine-A/T-ECU <A/T>

Refer to P.13A-8, INSPECTION CHART FOR DIAGNOSIS CODES.

Check the harness wire between combination meter and engineECU <M/T> or engine-A/T-ECU <A/T> connector, and repair if necessary.

Page 48

13A-48

INSPECTION PROCEDURE 5

MPI <4G6> -

Troubleshooting

No initial combustion (starting impossible)

In cases such as the above, the cause is probably that a spark plug is defective, or that the supply of fuel to the combustion chamber is defective. In addition, foreign materials (water, kerosene, etc.) may be mixed with the fuel.

Check battery voltage when cranking.

OK:

8 V or higher

Is immobilizer-ECU diagnosis code displayed?

MUT-IIData list

16 Power supply voltage (Refer to P.13A-75.)

Does the camshaft rotate at the engine cranking? (When oil filler cap is removed.)

Yes

MUT-IISelf-Diag code

Are diagnosis codes displayed?

MUT-IIData list

22 Crank angle sensor

OK:

Cranking speed is displayed

MUT-IIActuator test

07 Fuel pump (Refer to P.13A-80.)

MUT-IIData list

21 Engine coolant temperature sensor (Refer to P.13A-75.)

Can any sound be heard from the injectors when cranking?

Yes

Measure at the ignition coil connectors B-01 and B-11

Connectors connected

Check by connecting the timing light to terminal 1 of each

connector (Engine: Cranking)

OK:

The timing light flashes.

Yes

Check the battery. (Refer to GROUP 54 - Battery.)

Check the immobilizer. (Refer to GROUP 54 - Ignition Key and Immobilizer.)

Check the power supply and ignition switch-IG system. (Refer to P.13A-69, INSPECTION PROCEDURE 27.)

Check timing belt for breakage.

Refer to P.13A-8, INSPECTION CHART FOR DIAGNOSIS CODES.

Check the crank anglesensor system.(Refer to P.13A-32,INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0335.)

Check the fuel pump system. (Refer to P.13A-69, INSPECTION PROCEDURE 28.)

Check the engine coolant temperature sensor system. (RefertoP.13A-16,INSPECTIONPROCEDURE FORDIAGNOSIS CODE P0115.)

Check the injector system. (Refer to P.13A-28, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0201, P0202, P0203,P0204.)

Check the ignition circuit system. (Refer to P.13A-72, INSPECTION PROCEDURE 31.)

Probable cause

Malfunction of the ignition system

Malfunction of the fuel pump system

Malfunction of the injectors

Malfunction of the engine-ECU <M/T> or

engine-A/T-ECU <A/T> Malfunction of the immobilizer system

Foreign materials in fuel

Check the following items.

Check the ignition coil, spark plugs, spark plug cables.

Check if the injectors are clogged.

Check if foreign materials (water, alcohol, etc.) got into fuel.

Check the compression pressure.

Check the immobilizer system.

Page 49

INSPECTION PROCEDURE 6

MPI <4G6> -

Troubleshooting

13A-49

Initial combustion but no complete combustion (starting impossible)

In such cases as the above, the cause is probably that the spark plugs are generating sparks but the sparks are weak, or the initial mixture for starting is not appropriate.

Check battery voltage when cranking.

OK:

8 V or higher

MUT-IISelf-Diag code

Are diagnosis codes displayed?

MUT-IIActuator test

07 Fuel pump (Refer to P.13A-80.)

MUT-IIData list

21 Engine coolant temperature sensor (Refer to P.13A-75.)

MUT-IIData list

18 Ignition switch-ST (Refer to P.13A-75.)

Can any sound be heard from the injectors when cranking?

Is starting good if the engine is cranked with the accelerator pedal slightly depressed?

Yes

Check the battery. (Refer to GROUP 54 - Battery.)

Refer to P.13A-8, INSPECTION CHARTFOR DIAGNOSIS CODE.

Check the fuel pump system. (Refer to P.13A-69, INSPECTION PROCEDURE 28.)

Check the engine coolant temperature sensor system. (RefertoP.13A-16,INSPECTIONPROCEDURE FORDIAGNOSIS CODE P0115.)

Check the ignition switch-ST system. (Refer to P.13A-71, INSPECTION PROCEDURE 29.)

Check the injector system. (Refer to P.13A-28, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0201, P0202, P0203,P0204.)

Check ISC servo for operation sound. (Refer to P.13A-95*.)

Probable cause

Malfunction of the ignition system

Malfunction of the injector system

Foreign materials in fuel

Poor compression

Malfunction of the engine-ECU <M/T> or

engine-A/T-ECU <A/T>

Check the ISC servo system. (Refer to P.13A-39, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0505.)

Clean the throttle valve area. (Refer to P.13A-81*.)

Check and adjust the fixed SAS. (Refer to P.13A-83*.)

Check the ignition timing when cranking.

OK:

Approx. 5_BTDC

Check the following items.

Check the ignition coil, spark plugs, spark plug cables.

Check if the injectors are clogged.

Check the compression pressure.

Check fuel lines for clogging.

Check if foreign materials (water, alcohol, etc.) got into fuel.

Check that the crank angle sensor is installed properly.

NOTE: *: Refer to the ’97 GALANT Workshop Manual (Pub. No. PWDE9611)

Page 50

13A-50

INSPECTION PROCEDURE 7

MPI <4G6> -

Troubleshooting

It takes too long time to start. (Incorrect starting)

In cases such as the above, the cause is probably that the spark is weak and ignition is difficult, the initial mixture for starting is not appropriate, or sufficient compression pressure is not being obtained.

Check battery voltage when cranking

OK:

8 V or higher

MUT-IISelf-Diag code

Are diagnosis codes displayed?

MUT-IIActuator test

07 Fuel pump (Refer to P.13A-80.)

MUT-IIData list

21 Engine coolant temperature sensor (Refer to P.13A-75.)

MUT-IIData list

18 Ignition switch-ST (Refer to P.13A-75.)

Can any sound be heard from the injectors when cranking?

Check the ignition timing when cranking.

OK:

Approx. 5_BTDC

Yes

Check the battery. (Refer to GROUP 54 - Battery.)

Refer to P.13A-8, INSPECTION CHARTFOR DIAGNOSIS CODE.

Check the fuel pump system. (Refer to P.13A-69, INSPECTION PROCEDURE 28.)

Check the engine coolant temperature sensor system. (RefertoP.13A-16,INSPECTIONPROCEDURE FORDIAGNOSIS CODE P0115.)

Check the ignition switch-ST system. (Refer to P.13A-71, INSPECTION PROCEDURE 29.)

Check the injector system. (Refer to P.13A-28, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0201, P0202, P0203,P0204.)

Check that the crank angle sensor is installed properly.

Probable cause

Malfunction of the ignition system

Malfunction of the injector system

Inappropriate gasoline use

Poor compression

Check the following items.

Check the ignition coil, spark plugs, spark plug cables.

Check if the injectors are clogged.

Check the compression pressure.

Check if foreign materials (water, alcohol, etc.) got into fuel.

Page 51

INSPECTION PROCEDURE 8

MPI <4G6> -

Troubleshooting

13A-51

Unstable idling (Rough idling, hunting)

In cases as the above, the cause is probably that the ignition system, air/fuel mixture, idle speed control (ISC) or compression pressure is defective. Because the range of possible causes is broad, inspection is narrowed down to simple items.

Were the battery terminals disconnected?

MUT-IISelf-Diag code

Are diagnosis codes displayed?

Does idling speed fluctuate excessively?

Check the ISC servo for operation sound. (Refer to P.13A-95*.)

Check the injector for operation sound.

MUT-IIData list

26 Idle position switch (Refer to P.13A-75.)

MUT-IIData list

13 Intake air temperature sensor (Refer to P.13A-75.)

MUT-IIData list

25 Barometric pressure sensor (Refer to P.13A-75.)

MUT-IIData list

21 Engine coolant temperature sensor (Refer to P.13A-75.)

MUT-IIActuator test

08 Purge control solenoid valve (Refer to P.13A-80.)

MUT-IIActuator test

10 EGR control solenoid valve (Refer to P.13A-80.)

Yes

After warming-up, let the engine run at idling for 10 minutes.

Refer to P.13A-8, INSPECTION CHART FOR DIAGNOSIS CODES.

Clean the throttle body. (Refer to P.13A-81*.)

Check and adjust the fixed SAS. (Refer to P.13A-83*.)

Check trouble symptom.

Inspect the intake of air into the air intake system

D D D D

Check the ISC system. (Refer to P.13A-39, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0505.)

Check the injector system. (Refer to P.13A-28, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0201, P0202, P0203,P0204.)

Check the idleposition switch system. (Refer to P.13A-41, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0510.)

Checkthe intake air temperature sensor system. (Refer toP.13A-14, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0110.)

Check the barometric pressure sensor system. (Refer to P.13A-12, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0105.)

Check the engine coolant temperature sensor system. (RefertoP.13A-16,INSPECTIONPROCEDURE FORDIAGNOSIS CODE P0115.)

Check the purge control solenoid valve system (RefertoP.13A-38,INSPECTIONPROCEDURE FORDIAGNOSIS CODE P0443.)

Check the EGR control solenoid valve system. (Refer to P.13A-36, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0403.)

Probable cause

Malfunction of the ignition system

Malfunction of air/fuel ratio control system

Malfunction of the ISC system

Malfunction of the purge control solenoid valve system

Malfunction of the EGR solenoid valve system

Poor compression

Drawing air into exhaust system

Broken intake manifold gasket Broken air intake hose Broken vacuum hose Positive crankcase ventilation valve does not operate.

To the next page

NOTE: *: Refer to the ’97 GALANT Workshop Manual (Pub. No. PWDE9611)

Page 52

13A-52

From the previous page

MUT-IIData list

59 Oxygen sensor (rear)

Transmission: 2nd gear <M/T>, L range <A/T>

Driving with throttle widely open

OK:

600 - 1,000 mV

MUT-IIData list

11 Oxygen sensor

OK:

600 - 1,000 mV during sudden racing

MUT-IIData list

11 Oxygen sensor

OK:

Changes between 0 - 400 mV and 600 - 1,000 mV during idling

MUT-IIData list

27 Power steering fluid pressure switch (Refer to P.13A-75.)

MUT-IIData list

28 A/C switch (Refer to P.13A-75.)

MUT-IIData list

29 Inhibitor switch (Refer to P.13A-75.)

MUT-IIData list

45 ISC Servo position (Refer to P.13A-61.)

Check the ignition timing. (Refer to GROUP 11A - On-vehicle Service.)

MPI <4G6> -

Troubleshooting

Check the oxygen sensor (rear) system. (Refer to P.13A-24, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0136.)

Check the oxygen sensor (front) system. (Refer to P.13A-21, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0130.)

Check the fuel pressure. (Refer to P.13A-85*.)

Check the power steering fluid pressure switch system. (Refer to P.13A-42, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0551.)

Check the A/C switch and A/C relay system. (Refer to P.13A-72, INSPECTION PROCEDURE 30.)

Check the ignition switch-ST. (Refer to P.13A-71, INSPECTION PROCEDURE 29.)

Adjust the basic idle speed. (Refer to P.13A-83*.)

Check that the crank angle sensor is installed properly.

1. Inspect the intake of air into the air intake system.

Broken intake

manifold gasket Broken vacuum

hose PCV valve does

not operate. Broken air intake

hose

2. Check the injector for clog.

Check the following items.

Check the ignition coil, spark plugs, spark plug cables.

Check the purge control system.

Check the EGR control system.

Check the compression pressure.

Check if foreign materials (water, alcohol, etc.) got into fuel.

NOTE: *: Refer to the ’97 GALANT Workshop Manual (Pub. No. PWDE9611)

Page 53

INSPECTION PROCEDURE 9

MPI <4G6> -

Troubleshooting

13A-53

Idling speed is high. (Improper idling speed)

In such cases as the above, the cause is probably that the intake air volume during idling is too great.

MUT-IISelf-Diag code

Are diagnosis codes displayed?

Check the ISC servo for operation sound. (Refer to P.13A-95*.)

MUT-IIData list

26 Idle position switch (Refer to P.13A-75.)

MUT-IIData list

21 Engine coolant temperature sensor (Refer to P.13A-75.)

MUT-IIData list

28 A/C switch (Refer to P.13A-75.)

Basic idle adjustment (Refer to P.13A-83*.)

Check trouble symptom.

Yes

Refer to P.13A-8, INSPECTION CHART FOR DIAGNOSIS CODES.

Check the ISC system. (Refer to P.13A-39, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0505.)

Check the idleposition switch system. (Refer to P.13A-41, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0510.)

Check the engine coolant temperature sensor system. (RefertoP.13A-16,INSPECTIONPROCEDURE FORDIAGNOSIS CODE P0115.)

Check the A/C switch and A/C relay system. (Refer to P.13A-72, INSPECTION PROCEDURE 30.)

Clean the throttle valve area. (Refer to P.13A-81*.)

Probable cause

Malfunction of the ISC system

Malfunction of the throttle body

Check and adjust the fixed SAS. (Refer to P.13A-83*.)

NOTE: *: Refer to the ’97 GALANT Workshop Manual (Pub. No. PWDE9611)

Page 54

13A-54

INSPECTION PROCEDURE 10

MPI <4G6> -

Troubleshooting

Idling speed is low. (Improper idling speed)

In cases such as the above, the cause is probably that the intake air volume during idling is too small.

MUT-IISelf-Diag code

Are diagnosis codes displayed?

Check the ISC servo for operation sound. (Refer to P.13A-95*.)

MUT-IIData list

26 Idle position switch (Refer to P.13A-75.)

MUT-IIData list

21 Engine coolant temperature sensor (Refer to P.13A-75.)

MUT-IIData list

29 Inhibitor switch (Refer to P.13A-75.)

Basic idle adjustment (Refer to P.13A-83*.)

Check trouble symptom.

Yes

Refer to P.13A-8, INSPECTION CHART FOR DIAGNOSIS CODES.

Check the ISC system. (Refer to P.13A-39, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0505.)

Check the idleposition switch system. (Refer to P.13A-18, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0120.)

Check the engine coolant temperature sensor system. (RefertoP.13A-16,INSPECTIONPROCEDURE FORDIAGNOSIS CODE P0115.)

Check the ignition switch ST. (Refer to P.13A-71, INSPECTION PROCEDURE 29.)

Clean the throttle valve area. (Refer to P.13A-81*.)

Probable cause

Malfunction of the ISC system

Malfunction of the throttle body

Check and adjust the fixed SAS. (Refer to P.13A-83*.)

NOTE: *: Refer to the ’97 GALANT Workshop Manual (Pub. No. PWDE9611)

Page 55

INSPECTION PROCEDURE 11

MPI <4G6> -

Troubleshooting

13A-55

When the engine is cold, it stalls at idling. (Die out)

Insuch cases as theabove, thecause is probablythattheair/fuelmixture is inappropriate when the engine is cold, or that the intake air volume is insufficient.

Were the battery terminals disconnected?

MUT-IISelf-Diag code

Are diagnosis codes displayed?

Does the engine stall right after the accelerator pedal is released?

Is engine-idling stable after the warming-up?

Yes

Check the ISC servo for operation sound. (Refer to P.13A-95*.)

Check the injector for operation sound.

MUT-IIData list

26 Idle position switch (Refer to P.13A-75.)

MUT-IIData list

21 Engine coolant temperature sensor (Refer to P.13A-75.)

MUT-IIActuator test

10 EGR control solenoid valve (Refer to P.13A-80.)

Check the fuel pressure. (Refer to P.13A-85*.)

Check the ignition timing. (Refer to GROUP 11A - On-vehicle Service.)

Yes

After warming-up, let the engine run at idling for 10 minutes.

Refer to P.13A-8, INSPECTION CHART FOR DIAGNOSIS CODES.

Clean the throttle valve area. (Refer to P.13A-81*.)

Check if the unstable idling (Rough idling, hunting). (Refer to P.13A-51, INSPECTION PROCEDURE 8.)

Check the ISC system. (Refer to P.13A-39, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0505.)

Check the injector system. (Refer to P.13A-28, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0201, P0202, P0203,P0204.)

Check the idleposition switch system. (Refer to P.13A-41, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0510.)

Check the engine coolant temperature sensor system. (RefertoP.13A-16,INSPECTIONPROCEDURE FORDIAGNOSIS CODE P0115.)

Check the EGR control solenoid valve system. (Refer to P.13A-36, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0403.)

Check that the crank angle sensor is installed properly.

Probable cause

Malfunction of the ISC system

Malfunction of the throttle body

Malfunction of the injector system

Malfunction of the ignition system

Check and adjust the fixed SAS. (Refer to P.13A-83*.)

Check the following items.

Check the ignition coil, spark plugs, spark plug cables.

Check the compression pressure.

Check the engine oil viscosity.

NOTE: *: Refer to the ’97 GALANT Workshop Manual (Pub. No. PWDE9611)

Page 56

13A-56

INSPECTION PROCEDURE 12

MPI <4G6> -

Troubleshooting

When the engine is hot, it stalls at idling. (Die out)

In such cases as the above, the cause is probably that ignition system, air/fuel mixture, idle speed control (ISC) or compression pressure is defective. In addition, if the engine suddenly stalls, the cause may also be a defective connector contact.

Were the battery terminals disconnected?

MUT-IISelf-Diag code

Are diagnosis codes displayed?

Check the ISC servo for operation sound. (Refer to P.13A-95*.)

Check the injector for operation sound.

Does the engine stall right after the accelerator pedal is released?

Does the engine stall easily again?

Yes

After warming-up, let the engine run at idling for 10 minutes.

Refer to P.13A-8, INSPECTION CHART FOR DIAGNOSIS CODES.

Check the ISC system. (Refer to P.13A-39, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0505.)

Check the injector system. (Refer to P.13A-28, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0201, P0202, P0203,P0204.)

Clean the throttle valve area. (Refer to P.13A-81*.)

While carrying out an intermittent malfunction simulation test (Refer to GROUP 00 - Points to Note forIntermittent Malfunctions.),check for sudden changes in the signals shown below.

D D D D

Probable cause

Malfunction of the ignition system

Malfunction of air/fuel ratio control system

Malfunction of the ISC system

Drawing air into intake system

Improper connector contact

Crank angle sensor signal Air flow sensor signal Injector drive signal Primary and secondary ignition signal

D D

Check and adjust the fixed SAS. (Refer to P.13A-83*.)

Fuel pump drive signal Engine-ECU <M/T> or engine-A/T-ECU <A/T> power supply voltage

MUT-IIData list

26 Idle position switch (Refer to P.13A-75.)

MUT-IIData list

13 Intake air temperature sensor (Refer to P.13A-75.)

MUT-IIData list

25 Barometric pressure sensor (Refer to P.13A-75.)

MUT-IIData list

21 Engine coolant temperature sensor (Refer to P.13A-75.)

MUT-IIActuator test

10 EGR control solenoid valve (Refer to P.13A-80.)

MUT-IIData list

59 Oxygen sensor (rear)

Transmission: 2nd gear <M/T>, L range <A/T>

Driving with throttle widely open

OK:

600 - 1,000 mV

To the next page

Check the idleposition switch system. (Refer to P.13A-41, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0510.)

Checkthe intake air temperature sensor system. (Refer toP.13A-14, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0110.)

Check the barometric pressure sensor system. (Refer to P.13A-12, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0105.)

Check the engine coolant temperature sensor system. (RefertoP.13A-16,INSPECTIONPROCEDURE FORDIAGNOSIS CODE P0115.)

Check the EGR control solenoid valve system. (Refer to P.13A-36, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0403.)

Check the oxygen sensor (rear) system. (Refer to P.13A-24, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0136.)

NOTE: *: Refer to the ’97 GALANT Workshop Manual (Pub. No. PWDE9611)

Page 57

MPI <4G6> -

From the previous page

MUT-IIData list

11 Oxygen sensor

OK:

Changes between 600 - 1,000 mV during sudden racing

MUT-IIData list

11 Oxygen sensor

OK:

Changes between 0 - 400 mV and 600 - 1,000 mV during idling

MUT-IIData list

27 Power steering fluid pressure switch (Refer to P.13A-75.)

MUT-IIData list

28 A/C switch (Refer to P.13A-75.)

MUT-IIData list

29 Inhibitor switch (Refer to P.13A-75.)

MUT-IIData list

45 ISC servo position (Refer to P.13A-75.)

Check the ignition timing. (Refer to GROUP 11A - On-vehicle Service.)

Troubleshooting

Check the oxygen sensor (front) system. (Refer to P.13A-21, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0130.)

Check the fuel pressure. (Refer to P.13A-85*.)

Check the power steering fluid pressure switch system. (Refer to P.13A-42, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0551.)

Check the A/C switch and A/C relay system. (Refer to P.13A-72, INSPECTION PROCEDURE 30.)

Check the ignition switch-ST. (Refer to P.13A-71, INSPECTION PROCEDURE 29.)

Adjust the basic idle speed. (Refer to P.13A-83*.)

Check that the crank angle sensor is installed properly.

13A-57

1. Inspect the intake of air into the air intake system

Broken intake

manifold gasket Broken vacuum

hose PCV valve does

not operate. Broken air intake

hose

2. Check the injector for clog.

Check the following items.

Check the ignition coil, spark plugs, spark plug cables.

Check if the injectors are clogged.

Check the compression pressure.

Check if foreign materials (water, alcohol, etc.) got into fuel.

NOTE: *: Refer to the ’97 GALANT Workshop Manual (Pub. No. PWDE9611)

Page 58

13A-58

INSPECTION PROCEDURE 13

MPI <4G6> -

Troubleshooting

The engine stalls when starting the car. (Pass out)

In cases such as the above, the cause is probably misfiring due to a weak spark, or an inappropriate air/fuel mixture when the accelerator pedal is depressed.

MUT-IISelf-Diag code

Are diagnosis codes displayed?

MUT-IIActuator test

10 EGR control solenoid valve (Refer to P.13A-80.)

Check the following items.

Check the ignition coil, spark plugs, spark plug cables.

Check if air was drawn into the intake system.

Broken intake manifold gasket Broken or disconnected vacuum hose Improper operation of the PCV valve Broken air intake hose

Yes

INSPECTION PROCEDURE 14

The engine stalls when decelerating.

In cases such asthe above, thecause isprobably that theintake airvolumeis insufficient due to a defective idle speed control (ISC) system.

Were the battery terminals disconnected?

MUT-IISelf-Diag code

Are diagnosis codes displayed?

MUT-IIData list

26 Idle position switch (Refer to P.13A-75.)

MUT-IIData list

14 Throttle position sensor (Refer to P.13A-75.)

MUT-IIData list

45 ISC servo position

Is the idle speed control (ISC) servo position drops to 0 - 2

steps when decelerating (engine r/min less than 1,000)?

MUT-IIActuator test

10 EGR control solenoid valve (Refer to P.13A-80.)

Yes

Probable cause

Drawing air into intake system

Malfunction of the ignition system

Refer to P.13A-8, INSPECTION CHART FOR DIAGNOSIS CODES.

Check the EGR control solenoid valve system. (Refer to P.13A-36, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0403.)

Probable cause

Malfunction of the ISC system

After warming-up, let the engine run at idling for 10 minutes.

Refer to P.13A-8, INSPECTION CHART FOR DIAGNOSIS CODES.

Check the idleposition switch system. (Refer to P.13A-41, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0510.)

Check the throttle position sensor system. (Refer to P.13A-18, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0120.)

Check the vehicle speed sensor system. (Refer to P.13A-39, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0500.)

Check the EGR control solenoid valve system. (Refer to P.13A-36, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0403.)

Check the following items.

Check the ignition coil, spark plugs, spark plug cables.

Clean the throttle valve area.

Check and adjust the fixed SAS.

Page 59

INSPECTION PROCEDURE 15

MPI <4G6> -

Troubleshooting

13A-59

Hesitation, sag or stumble

In cases such as the above, the cause is probably that ignition system, air/fuel mixture or compression pressure is defective.

MUT-IISelf-Diag code

Are diagnosis codes displayed?

Check the injectors for operation sound.

Check the ignition timing. (Refer to GROUP 11A - On-vehicle Service.)

MUT-IIData list

26 Idle position switch (Refer to P.13A-75.)

MUT-IIData list

13 Intake air temperature sensor (Refer to P.13A-75.)

MUT-IIData list

25 Barometric pressure sensor (Refer to P.13A-75.)

MUT-IIData list

21 Engine coolant temperature sensor (Refer to P.13A-75.)

MUT-IIData list

14 Throttle position sensor (Refer to P.13A-75.)

MUT-IIActuator test

10 EGR control solenoid valve (Refer to P.13A-80.)

MUT-IIData list

59 Oxygen sensor (rear)

Transmission: 2nd gear <M/T>, L range <A/T>

Driving with throttle widely open

: 600 - 1,000 mV

MUT-IIData list

11 Oxygen sensor

OK:

Changes between 600 - 1,000 mV during sudden racing

Yes

Refer to P.13A-8, INSPECTION CHART FOR DIAGNOSIS CODES.

Check the injector system. (Refer to P.13A-28, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0201, P0202, P0203,P0204.)

Check that the crank angle sensor is installed properly.

Check the idle position switch system. (RefertoP.13A-41,INSPECTIONPROCEDURE FORDIAGNOSIS CODE P0510.)

Checkthe intake air temperature sensor system. (Refer toP.13A-14, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0110.)

Check the barometric pressure sensor system. (Refer to P.13A-12, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0105.)

Check the engine coolant temperature sensor system. (RefertoP.13A-16,INSPECTIONPROCEDURE FORDIAGNOSIS CODE P0115.)

Check the throttle position sensor system. (Refer to P.13A-18, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0120.)

Check the EGR control solenoid valve system. (RefertoP.13A-36,INSPECTIONPROCEDURE FORDIAGNOSIS CODE P0403.)

Check the oxygen sensor (rear) system. (Refer to P.13A-24, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0136.)

Check the oxygen sensor (front) system. (Refer to P.13A-21, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0130.)

Probable cause

Malfunction of the ignition system

Malfunction of air/fuel ratio control system

Malfunction of the fuel supply system

Malfunction of the EGR control solenoid valve system

Poor compression

To the next page

Page 60

13A-60

From the previous page

MUT-IIData list

11 Oxygen sensor

OK:

Changes between 0 - 400 mV and 600 - 1,000 mV during idling

Check the fuel pressure. (Refer to P.13A-85*.)

Check the following items.

Check the ignition coil, spark plugs, spark plug cables.

Check the EGR control system.

Check the compression pressure.

Check the fuel filter or fuel line for clogging.

MPI <4G6> -

Troubleshooting

Check the fuel pressure. (Refer to P.13A-85*.)

NOTE: *: Refer to the ’97 GALANT Workshop Manual (Pub. No. PWDE9611)

INSPECTION PROCEDURE 16

1. Inspect the intake of air into the air intake system

Broken intake

manifold gasket Broken vacuum

hose PCV valve does

not operate. Broken air intake

hose

2. Check the injector for clog.

The feeling of impact or vibration when accelerating

In cases such as the above, the cause is probably that there is an ignition leak accompanying the increase in the spark plug demand voltage during acceleration.

MUT-IISelf-Diag code

Are diagnosis codes displayed?

Check the following items.

Check the ignition coil, spark plugs, spark plug cables.

Check for occurrence of ignition leak.

Yes

INSPECTION PROCEDURE 17

The feeling of impact or vibration when decelerating.

Malfunction of the ISC system is suspected.

MUT-IISelf-Diag code

Are diagnosis codes displayed?

Check the ISC servo for operation sound. (Refer to P.13A-95*.)

MUT-IIData list

14 Throttle position sensor (Refer to P.13A-75.)

MUT-IIData list

26 Idle position switch (Refer to P.13A-75.)

Clean the throttle valve area. (Refer to P.13A-81*.)

Yes

Probable cause

Malfunction of the ignition system

Refer to P.13A-8, INSPECTION CHART FOR DIAGNOSIS CODES.

Probable cause

Malfunction of the ISC system

Refer to P.13A-8, INSPECTION CHART FOR DIAGNOSIS CODES.

Check the ISC system. (Refer to P.13A-39, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0505.)

Check the throttle position sensor system. (Refer to P.13A-18, INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0120.)

Check the idle position switch system. (RefertoP.13A-41,INSPECTIONPROCEDURE FORDIAGNOSIS CODE P0510.)

NOTE: *: Refer to the ’97 GALANT Workshop Manual (Pub. No. PWDE9611)

Page 61

INSPECTION PROCEDURE 18

MPI <4G6> -

Troubleshooting

13A-61

Poor acceleration

Defective ignition system, abnormal air/fuel ratio, poor compression pressure, etc. are suspected.