THIS PRODUCT MAY BE USED SOLELY ON VEHICLES USED IN SANCTIONED COMPETITION WHICH MAY
NEVER BE USED UPON A PUBLIC ROAD OR HIGHWAY, UNLESS PERMITTED BY SPECIFIC REGULATORY
EXEMPTION. (VISIT THE “EMISSIONS” PAGE AT HTTP://WWW.SEMASAN.COM/EMISSIONS FOR STATE BY
STATE DETAILS.)
IT IS THE RESPONSIBILITY OF THE INSTALLER AND/OR USER OF THIS PRODUCT TO ENSURE THAT IT IS
USED IN COMPLIANCE WITH ALL APPLICABLE LAWS AND REGULATIONS. IF YOU HAVE PURCHASED
THIS PRODUCT IN ERROR, DO NOT INSTALL AND/OR USE IT. PLEASE CONTACT THE RETAILER FROM
WHOM YOU PURCHASED THE PRODUCT TO ARRANGE A RETURN FOR A FULL REFUND OR VISIT
AEMELECTRONICS.COM/PRODUCT-LEGAL-RESTRICTIONS FOR FURTHER INSTRUCTIONS.
Manual
30-71XX
Infinity
Quick Start Guide
WARNING: This installation is not for the tuning novice! Use this system with EXTREME caution! The AEM
Infinity Programmable EMS allows for total flexibility in engine tuning. Misuse or improper tuning of this
product can destroy your engine! If you are not well versed in engine dynamics and the tuning of engine
management systems DO NOT attempt the installation. Refer the installation to an AEM-trained tuning
shop or call 800-423-0046 for technical assistance.
NOTE: All supplied AEM calibrations, Wizards and other tuning information are offered as potential
starting points only. IT IS THE RESPONSIBILITY OF THE ENGINE TUNER TO ULTIMATELY CONFIRM IF THE
CALIBRATION IS SAFE FOR ITS INTENDED USE. AEM holds no responsibility for any engine damage that
results from the misuse or mistuning of this product!
AEM Performance Electronics, 2205 126th Street Unit A, Hawthorne, CA 90250
..........................................................................................................................................................22Calibration Data
..........................................................................................................................................................39VE & Airflow Based Tuning
..........................................................................................................................................................49Idle Air Control Valve Requirements
The latest firmware for your Infinity ECU is available at http://www.aeminfinity.com. Follow the
instructions in this manual to install InfinityTuner then go directly to aeminfinity.com to download
your firmware.
12 Month Limited Warranty
Advanced Engine Management Inc. warrants to the consumer that all AEM High Performance
products will be free from defects in material and workmanship for a period of twelve (12) months
from date of the original purchase. Products that fail within this 12-month warranty period will be
repaired or replaced at AEM’s option, when determined by AEM that the product failed due to
defects in material or workmanship. This warranty is limited to the repair or replacement of the
AEM part. In no event shall this warranty exceed the original purchase price of the AEM part nor
shall AEM be responsible for special, incidental or consequential damages or cost incurred due
to the failure of this product. Warranty claims to AEM must be transportation prepaid and
accompanied with dated proof of purchase. This warranty applies only to the original purchaser
of product and is non-transferable. All implied warranties shall be limited in duration to the said
12-month warranty period. Improper use or installation, accident, abuse, unauthorized repairs or
alterations voids this warranty. AEM disclaims any liability for consequential damages due to
breach of any written or implied warranty on all products manufactured by AEM. Warranty returns
will only be accepted by AEM when accompanied by a valid Return Merchandise Authorization
(RMA) number. Product must be received by AEM within 30 days of the date the RMA is issued.
Please note that before AEM can issue an RMA for any electronic product, it is first necessary
for the installer or end user to contact the EMS tech line at 1-800-423-0046 to discuss the
problem. Most issues can be resolved over the phone. Under no circumstances should a
system be returned or a RMA requested before the above process transpires.
AEM will not be responsible for electronic products that are installed incorrectly, installed in a
non-approved application, misused, or tampered with.
Any AEM electronics product can be returned for repair if it is out of the warranty period. There is
a minimum charge of $50.00 for inspection and diagnosis of AEM electronic parts. Parts used in
the repair of AEM electronic components will be extra. AEM will provide an estimate of repairs
and receive written or electronic authorization before repairs are made to the product.
The Infinity platform is very different from previous generation AEM EMS products. The hardware
(circuit board assembly) is designed around a very advanced automotive grade microcontroller
(processor or “chip”). Several layers of software reside on this chip that allow for real time
firmware programming without the need to write computer code. This technology has allowed
AEM to develop advanced control models never before used on other AEM EMS products.
We’ve listened to our customers over the years and have attempted to simplify the tuning
process by employing an airflow based fuel control model eliminating many of the lookup and
trim tables from previous generation ECUs. The look and feel is very different and it may take
some time to adjust to the new tuning environment.
Our new tuning tool, Infinity Tuner is also a brand new product built from the ground up to interface
with the new hardware. It features a modular design that allows users and developers to build
completely customized templates and even design “plug in” applications that can automate many
tuning tasks. Unlike previous AEM Setup Wizards in older products like AEM Pro and AEM
Tuner, the Infinity Tuner Setup Wizard “plug in” is a completely stand-alone application that will
evolve with Infinity Tuner. It is much more integrated with the ECU hardware and performs
complex validation checks for all requested changes.
Among other things, Infinity Tuner is a powerful math processor. Special features allow users to
create completely custom conversion channels for table data. Virtually any function can be
employed to display data in different formats or units. Math functions are also used for table
edits. ANY MATH function can be used not just a list of pre-defined selections. Advanced users
will really enjoy the flexibility this feature adds.
A built-in logging playback/controls synchronization feature allows tuners to view live plot data
and make changes to their calibration values on the fly, knowing exactly where the ECU was
accessing table data. For more detailed post processing of data, AEM offers its new analysis
package, AEMdata.
All current Infinity Tuner software installations and drivers are available for download from AEM
at http://www.aemelectronics.com/products/support
1. Run the setup.exe. Hit Next> and follow the instructions on each page.
2. Read and accept the terms of agreement and pick your desired location for Infinity Tuner to
be installed. Hit Next> and allow the software to complete installation.
3. You may now exit the Infinity Tuner installer. You can now run Infinity Tuner. To use Infinity
Tuner with an ECU connected first you will need to install the necessary drivers.
4. If desired, add a desktop link for InfinityTuner. Click the Windows Start button and navigate to
All Programs\InfinityTuner. Right click on the InfinityTuner link and select Send to>Desktop
(create shortcut).
Device Driver Installation
USB drivers are installed automatically as of Infinity Tuner version 2.95.7043. If installation
problems occur, follow the procedure below to manually install the drivers.
USB drivers are available for download from http://www.aemelectronics.com/products/support
A step by step guide for driver installation is documented in the following video...or copy and
paste the following link into a web browser:
http://www.youtube.com/watch?v=i5AY2MFmnzI
1. For these next steps the Infinity ECU will need to be installed and powered up. Refer to your
harness instructions details. You will need the ignition key in the on position. Connect your
computer to the ECU via the USB cable.
For Windows 7 users you may simply search for and open the “Device manager” using
the search bar under the start tab. You should see a window that looks similar to the
Device manager shown above on the left hand side.
For Window XP users right click on “My Computer” under the start tab. Click on
“Manage.” Select “Device Manager.” You should see a window that looks similar to the
Device manager shown above on the right hand side.
3. Next look for a device labeled something close to “AEM Infinity-10 EMS.” It may be listed
under “Other devices.” Right click “AEM Infinity-10 EMS” and select Update Driver Software.
When prompted with “How do you want to search for driver software?” select the second
option, “Browse my computer for driver software Locate and install driver software manually.”
USB driver files can be downloaded from http://www.aemelectronics.com/catalog-software-
downloads-72/
Save this file in an easy to find location like the Windows Desktop. You will need this link below.
**If AEM Infinity-10 EMS does not appear on the list please verify that the USB plug is
securely plugged into your computer and the ECU. Also make sure that the ECU is in fact
powered up and connected correctly. If problem persists, try turning the key off and then back to
the on position or try a different USB port on the PC.
4. Hit Browse and select the “AEM_Drivers_Signed” folder. Make sure to have the “Include
subfolders” box checked. Hit next. This will install the driver software onto your computer. You
will now be able to use the “Connect to USB” option in InfinityTuner.
AEM recom mends restarting your PC after making changes to your device driver installation.
Note: To confirm the driver installed properly you can return to your device manager window. The
“AEM Infinity-10 EMS” device will now be recognized and fall under the tab “AEM EMS
Controllers.”
AEM supplied layout files will come pre-loaded with several “Plot Control” windows. (Users can
always add, delete or edit them as desired.) These are special controls that allow real time data
logging and playback. To begin a PC log, go to the Log menu and select Start recording or hit
the “CTRL + L” hot key. Select Stop recording or hit the “CTRL + L” hot key again to stop
logging. A dialog will ask if you want to save the data or not. If you select “Yes,” you will be
prompted to save the current session file. A session file contains all the current configuration and
calibration data along with a log file. If you open that session file again, the file will be loaded and
all plot controls will be populated with the recorded data.
Plot Window Tools
Selection tool: Choose this icon by clicking on it then left click and drag through the plot
window to view current data values.
Pan tool: Choose this icon by clicking on it then left click and drag through the plot window
to pan the data left or right. Hot Key – Left/Right arrow
Zoom tool: Choose this icon by clicking on it then left click and drag up and down to zoom in
and out. Alternatively, a mouse scroll wheel can be used after selecting the zoom tool. Hot Key –
Up arrow/Page up, Down arrow/Page down
Additional hot keys available in plot control window:
Home – Brings you to the start of the log
End – Brings you to the end of the log
For Home and End, the current display range is kept, so if viewing 10 seconds worth of data,
Home will display the first 10 seconds while End will display the last 10 seconds.
Controls Synchronization
When the plot control is populated with data, using the selection tool and dragging through the
plot will cause Infinity Tuner to synchronize all control windows to the plot data. This happens
when connected to the simulator offline or when connected to the ECU via USB. To go back to
viewing “live” data, go to the Log menu and select Goto live data.
The image above shows plot data sync’d to control windows. All table cursors update with their
position relative to the logged data in the plot control. Note that in this mode, table edits are still
possible.
All Infinity ECUs are serialized. Be sure this identification tag stays intact. Write the number down
to be safe. Infinity ECUs are programmed with cryptographically secure firmware files and each
ECU has a unique file set. The serial number is used to identify the correct files for your ECU.
a. Plug the USB cable from the ECU into your computer USB port and key ignition ON.
b. Open Infinity Tuner.
2) Click the Target drop-down list and select “Upgrade firmware…”
19
3) The ECU should not be running an engine at this time. Select “Yes” when the warning
message appears.
Note: The firmware update utility is periodically updated and may not match the descriptions
below. In the event of a conflict, please follow the instructions provided in the dialog windows
themselves or supplemental instructions provided by AEM.
Important Note: BEFORE beginning the update process, be sure to have a saved copy
of your tuned session file. If a power failure occurs during the update process, this is
the only way to ensure that the calibration data is not lost.
a. Select the desired Configuration “Image” on the left.
i.If no images are present check C:\Program Files (x86)\AEM\Infinity Tuner\ and verify
.pakgrp file is there. If not, visit http://www.aeminfinity.com, log in, and download
appropriate file.
b. Ensure "Keep Calibration Data" check-box is marked to save current calibration.
c. Click the “Begin” button to start the upgrade process.
5) Follow the message at the bottom, and turn the ignition switch OFF when instructed to do so.
6) Follow the message at the bottom, and turn the ignition switch back ON when instructed to do
so.
7) When the message at the bottom indicates that it’s safe to close the window, click "X” button
on the top right of the window.
For applications that use a stepper motor idle valve, it's important that a full power reset
be done prior to starting the engine. Turn the key off and wait at least 20 seconds
before starting. This will allow the stepper valve to park and reset.
A firmware update will erase the USB log channel list stored in the ECU memory. This
channel list will need to be reset before USB logging will function correctly. See Log
Menu for more info.
Troubleshooting:
If the process hangs at any point, wait at least one minute for it to continue. Some PCs
take longer to reconnect to to the ECU during this process. Some PCs may have other
processes running that affect the response time of the USB ports. If the process has
not continued as described above after one minute, do not cycle key power. Instead,
remove the USB cable from the PC, wait a few seconds then plug it back in. Often this
will force the OS to reset the port allowing the process to continue.
Infinity Quick Start Guide
Tuning Guide
Basic Tuning
Calibration Data
Connecting, Saving and Importing Session Data
1) With the Ignition in the ON position and InfinityTuner Running, click on the Connection menu
item and select Connect to USB from the dropdown list. A progress bar will be displayed as
the laptop gets the calibration info from the ECU.
2) Open a layout file by clicking on the Layout menu item and select Open. Layout files have a
.itlyt extension and should be saved in the My Documents\InfinityTuner\Layouts folder.
3) Save the session file by selecting File – Save session. Session files have a .itssn extension
and should be saved in the My Documents\InfinityTuner folder.
The default calibration data provided by AEM should be sufficient to start an engine with similar
displacement, sensor setup, and injectors. Every vehicle must be tuned before use. AEM
provided base calibration data is installed to the My Documents\AEM\Infinity Tuner\Sessions
folder. To import calibration data from a saved session file, go to File > Import calibration data.
Wait a few moments for the operation to complete. Status messages are displayed during the
process notifying the user of each step along the way. If the import function is done while
connected to an ECU, after the import is complete:
1) Turn the key off and wait for the main relay to power down completely. This usually takes
about 10 seconds but depends on the model.
2) Turn the key back on.
Certain applications with CAN dash requirements must be powered down completely and
restarted after an import calibration. If this is not done, error lights may appear on the dash.
Please be aware of cross-platform differences that may require additional attention after
importing calibration data. For instance, the Digital7 pin is available on the Infinity-6 ECU but not
available on the Infinity-8H ECU. After importing Infinity-6 session data to an Infinity-8, any input
that was assigned to use Digital7 will be displayed as invalid in the wizard and needs to be
reassigned to work properly.
The ECU setup wizard is designed to simplify the initial configuration of the Infinity ECU. AEM
recommends using the wizard only when connected to the ECU via USB with the power
on. Most of the setup wizards require the engine to NOT be running. Exceptions will be clearly
stated in the function descriptions.
The setup wizard contains general and detailed descriptions with each major function. The most
imperative functions are discussed below. Use the descriptions in the wizard to assist in the
completion of all other setup features. New setup wizard features are being added constantly.
Please follow the written descriptions on each wizard page as this document may not accurately
represent the features included in the most recent versions.
The Setup Wizard is a stand alone application that runs in conjunction with Infinity Tuner. This
software is updated periodically and its appearance and features may not completely match the
descriptions below. In the event of a conflict, refer to the descriptions and instructions on the
Setup Wizard pages themselves.
With the laptop connected to the Infinity ECU via USB and InfinityTuner connected, go to the
Wizard menu at the top of the InfinityTuner layout and select Setup Wizard. Alternately, the hot
key combination [ALT]-[w]-[w]-[w] will launch the setup wizard.
The wizard is organized into different sections with expandable menu items on the left hand
pane. Use the highlighted arrow below in each section to expand the available sections.
Calibration data is automatically saved to ECU flash memory at key off if the "Key Off Commit"
function is selected in the Tuning preferences wizard page. Proper power sequencing is critical
in order to avoid problems. If power is removed from both pins C1-10 and C2-50 (Infinity 8/10/12
hardware) before this action is completed, the ECU may become inoperable and require
reprogramming at AEM.
If secondary injectors will be used, select this check box. A new fuel type menu is now visible
labeled Fuel Type (Secondary Injectors).
See Staged Injection for additional tuning information.
Note: If secondary injectors are being used, the option Has Secondary Injectors must be
selected and the table must be filled out indicating any injector number greater than the number
of engine cylinders as secondary. These selections must be made before restarting the ECU
and closing the form; otherwise an error will occur. See image below for a typical 6 cylinder
engine setup with 6 additional injectors classified as secondary. Note also the option to select a
different fuel type for primary and secondary.
This drop down menu contains the following setup information for primary (and secondary fuel
types, if selected).
-Gasoline
-Ethanol
-Methanol
-E85
-Flex Fuel
Phasing
The default injector phasing for the primary injectors is determined from the Firing Order
information from the Ignition Wizard. There is a fixed offset of 540 for injectors. After this offset is
added, the system checks to see if the result is less than 720. If the result of the calculation is
greater than or equal to 720, it is subtracted by 720 from that result
Lambda sensor assignment is determined by assigning a value of 1 or 2 to the InjXLambdaFB
channels. A value of 1 will assign the Lambda 1 sensor and a value of 2 will assign the Lambda 2
sensor. Min value = 1, Max value = 2
Allows the user to choose the proper reference pressure for the fuel pressure regulator. The drop
down menu has the following options:
Manifold Vacuum Reference: This should be selected if the fuel pressure regulator's port is
connected to a vacuum or vacuum/boost source.
Atmospheric Reference: This should be selected if the fuel pressure regulator's port is open to
atmosphere or if a dead end fuel system is used where fuel pressure is constant.
This database allows the user to select proper primary injector flow data.
InjFlowRate [cc/sec], 1-Axis lookup table of flow vs injector pressure.
InjOffset [us/10], 2-Axis lookup table of PW offset vs battery voltage and injector pressure
Secondary Injector Flow Selection
If Secondary Injectors were selected in the Injector Setup Wizard, this Secondary Injector Flow
Selection database will be enabled. This allows the user to select proper secondary injector flow
data.
InjSecFlowRate [cc/sec], 1-Axis lookup table of flow vs injector pressure.
InjSecOffset [us/10], 2-Axis lookup table of PW offset vs battery voltage and injector pressure
NOTE: If the Setup Wizard does not contain your specific fuel injector type, you can modify the
InjFlowRate table manually. If you do not know the different flow rates at different fuel pressures,
choose a flow rate (based on Manufacturers specs) at a known pressure and populate the entire
row with that value. For example, you have a fuel injector that is not listed in the Wizard Selection.
You know that it flows 475 cc/min at 45 psi. Select the cells in the upper row of the InjFlowRate
[cc/min] table and manually input 475. This will suffice to get the car up and running, though
proper flow data is ideal.
Set Throttle Range
The wizard displays a warning message to the user if the software is not connected to a
hardware target.
Live TPS Volts
Text and graphical representation of the raw analog voltage is shown.
Press this button when the throttle pedal is fully released. This will write the current value of
Analog7 [V] to the Throttle_raw [%] Analog In conditioner and display the resultant value on
the TPS Min Volts: X.XX display.
Set TPS Volts Max
Press this button after the throttle pedal is fully depresses. This will write the current value of
Analog7 [V] to the Throttle_raw [%] Analog In conditioner and display the resultant value on
the TPS Max Volts: X.XX display.
The engine's ignition timing must be synchronized with the Infinity Tuner's ignition timing display.
This is crucial with older vehicles that have adjustable distributors, adjustable cam angle sensors,
etc. Most modern engines do not utilize a manual adjustment for ignition timing. However, this
wizard should always be used for verification as sensors can be frequently installed backwards
or upside down. This can catch a problem before damage occurs.
Note: This wizard can only be used when the engine speed is greater than 50 RPM.
Ignition Timing
For synchronizing, the ignition timing can be locked by checking the box.
Allowable values: Min value = 0, Max value = 45
Sync Adjustment
The window includes 4 buttons. Two buttons are used to Advance Timing and TWO buttons
are used to Retard Timing.
The button labeled Large edits the CamSyncAdjustment TrigOffset [degBTDC] channel in
1.0 deg steps. The range is 0 to 719 degrees. The button labeled Small edits the TrigOffset
[degBTDC] channel in 0.1 deg steps.
The TrigOffset [degBTDC] is adjustable by Resolution. The Resolution setting has a range
of 0.25 deg to 2.0 degrees in 0.25 degree increments. This “stepping” function allows the
user to make TrigOffset [degBTDC] adjustments with the Small button up to the range limit.
Advanced Setup
Pickup sensor delay
The More and Less buttons increase/decrease the SpkDelayComp [us] value in
increments/decrements of 5.
Min value = 0, Max value = 500
Two separate procedures are required depending on the Infinity application: Plug and Play or
Universal Application.
Plug and Play
a. In the Ignition Sync wizard, select the checkbox “Lock ignition timing at” and set the “degrees
BTDC” (10.0 deg BTDC is the default).
b. Start the engine and use a timing light to verify that the crankshaft timing matches the locked
ignition timing set point (10.0 deg BTDC if using the default setting).
c. If there is a deviation between the locked set point and the actual timing observed with the
timing light, use the Sync Adjustment arrows to match the wizard-displayed value with the
actual value. As the Sync Adjustment arrows are advanced or retarded, the timing observed
on the crankshaft will change, while the “Lock ignition timing at 10.0 degrees BTDC” will
remain constant.
Universal Application
a. In the Ignition Sync wizard, select the checkbox “Lock ignition timing at” and set the “degrees
BTDC” (10.0 deg BTDC is the default).
b. Do NOT attempt to start the engine. Disable (unplug) the fuel injectors and/or fuel pump.
c. While cranking the engine, use a timing light to verify that the crankshaft timing matches the
locked ignition timing set point (10.0 deg BTDC if using the default setting).
d. If there is a deviation between the locked set point and the actual timing observed with the
timing light, use the Sync Adjustment arrows to match the wizard-displayed value with the
actual value. As the Sync Adjustment arrows are advanced or retarded, the timing observed
on the crankshaft will change, while the “Lock ignition timing at 10.0 degrees BTDC” will
remain constant.
e. Reconnect the fuel injectors and fuel pump.
f.Once the remaining Setup Wizards have been configured, repeat the Ignition Sync process
with the engine running to ensure that the crankshaft timing matches the locked ignition timing
set point.
Calibration table changes that haven't been committed to flash memory are highlighted as shown
below. Conditions that will reset the display are as follows:
1. Manually committing changes through the Target > Commit modifications menu command
2. Manually committing changes using the hot key combination [Ctrl Shift C]
3. Opening and closing the Setup Wizard. Note the Setup Wizard automatically commits ALL
changes to memory every time it is closed.
4. Turning the ignition switch off when the tuning preference Key Off Commit is selected
VE & Airflow Based Tuning
The Infinity ECU uses significantly different methods of calculating the fuel delivery requirements
and outputs than previous AEM products.
Measured data from sensors, i.e., Manifold Absolute Pressure (MAP [kPa]), Air Temperature,
Coolant Temperature, and Engine RPM, are acquired. The ECU uses this sensor data in
combination with Volumetric Efficiency (VE%) to estimate airflow.
The Volumetric Efficiency is a percentage of air and fuel that actually enters the cylinder during
induction relative to the volumetric capacity (rated displacement) of the cylinder under static
conditions. The VE lookup table is a 2-axis lookup table, with load values (typically MAP [kPa])
versus Engine RPM. In each table cell, the Engine RPM corresponds with a specific MAP [kPa],
and a Volumetric Efficiency is defined for that cell.
The Volumetric Efficiency is combined with temperature sensor data to estimate a compensated
Mass Airflow. The ChargeTempBlend table dictates what ratio of air temperature to coolant
temperature is used at specific Engine RPM to adjust the density of the inducted air. A higher
number gives priority to Coolant Temperature, and is seen at lower Engine RPM.
Once Mass Airflow has been calculated using the tables above, the Infinity ECU will look up the
Target Lambda (AFR) and then calculate the fuel requirements. Target AFR will be used as a
main parameter in determining fuel injector flow rate. The LambdaTargetTable (below Left) and
AFR Target Table conversion table (below Right) will have default values. Based on the
calculated Mass Airflow, the Infinity ECU will attempt to add enough fuel to hit the target AFR.
Note: The calculated LambdaTarget influences the fuel delivered to the engine at all
times, even when closed-loop 02 feedback is disabled.
The suggested tuning method is to set the AFR using the LambdaTargetTable or AFR Target
Table to a value safe and suitable for the engine. For normally aspirated engines a value of
13.0:1 or 0.887 lambda is usually sufficient at all operating conditions. For boosted applications,
the operating conditions dictate a safe AFR. Please consult a tuner knowledgeable in your
engine’s requirements for help. Once the target lambda (AFR) values are chosen, run the engine
at as many operating conditions as possible and adjust the VE Table to reach the AFR Target
Table values. Once the VE Table has been tuned to accurately reach the AFR Target Table
values at all operating ranges, then you can change the AFR Target Table to use different AFR
settings later. Never adjust VETable to run a different AFR, only to achieve the LambdaTarget
value.
The Injector Flowrate is very important in determining the fuel requirements. The Infinity ECU
uses actual Injector Flowrate [cc/min] to determine the proper injector pulse width. The
InjFlowRate [cc/min] table is calibrated from the Setup Wizard: Injector Flow, however the table
can be modified manually for unlisted injectors.
Now that the base injector flow rate has been determined, the Infinity ECU applies a few more
compensating factors. Wall Wetting is a function of fuel condensing in the intake manifold at the
injection point. At different rates of change in the MAP [kPa] values, and at different Coolant
Temperatures, fuel enrichment compensations are used to prevent lean and rich conditions
during rapid manifold pressure changes. Note that this table has several different functions. It can
be used for dynamic transients by nature of its “MAP Rate” x-axis. It can also be used for more
steady state compensations by adjusting the values in the “middle band” of the table where MAP
rate changes are very small. Positive numbers in this table will effectively add fuel to enrichen the
mixture. Negative numbers have the opposite effect.
The X and Y axis inputs of the WallWetting table can be set to several different variables. These
settings are found in the Setup Wizard page for Accel and Decel Fuel. Axis selections include:
A second WallWetting table is also available for even more transient fuel compensation
functionality. See the WallWetting2 Table topic for more information.
LamdaAfterStartTrim is a 2-axis table that is used to modify the Lambda (AFR) for specified
time after starting the engine. This table adds a lambda offset for a small period of time after the
engine is started. By allowing a slightly richer mixture target, it will keep the engine from stalling
or running rough immediately after starting and the lambda correction to a minimum. The last
column should be populated with “0” trim at operating temperatures to prevent a continuous
lambda offset.
To control the engine's fuel delivery system, the Infinity can be programmed to run open loop and/
or closed loop O2 feedback. Closed loop uses feedback from the oxygen sensor to make
temporary, but immediate, corrections to the injection to maintain a target air fuel ratio (AFR) or
lambda. The type of the O2 sensor will determine how lambda target can be controlled. Due to
the nature of standard narrow band O2 sensors, the only accurate measurement that can be
maintained in closed loop is Lambda 1.0. However, wideband O2 sensors can be used in
almost every feedback condition.
Note that 14.64:1 is called the stoichiometric AFR for gasoline. It is the ratio where all available
fuel is burned completely. For most performance applications, it is not the ideal AFR to operate
the engine at all the time nor is it the AFR that creates the most power or even economy under all
conditions.
When the fuel system is open loop, the O2 sensor is ignored and the injector pulse width relies
on the VE Table and fuel compensators to adjust injection duration. Open loop is necessary
during engine starts, when the O2 sensor has cooled below its operating temperature. It may
also be necessary when coolant temperatures are low. In this state, the fuel vaporization is poor
and the engine will require a richer mixture to properly operate. When under heavy load, the
engine typically requires an air fuel ratio that is out of a narrow band oxygen sensor's standard
range and open loop will be necessary. When the accelairflow function is triggered during hard
accelerations, open loop may be necessary to help stabilize the Target Lambda. Also, when the
deceleration function cuts fuel completely, target lambda will not be necessary.
LambaTargetTable
Units: Engine Load vs Engine Speed vs Lambda
Description: This table sets the target lambda for various engine conditions.
AEM recommends using the following proper crimp tool for all Infinity ECU terminations, Molex
Part No: 63811-4200. This tool is available in many places. One is shown below. Web address:
A cheaper, but lower quality, alternative is the following crimp tool, Molex Part No: 63811-1000.
This tool is available in many places. One is shown below. Web address: http://www.newark.com
Many Toyota, Mitsubishi, and other vehicles use an Idle Air Control Valve with a Unipolar Stepper
Motor (6-pin connector) and MUST be modified. See picture below. A Bipolar Stepper Motor
(e.g., GM) will have a 4-pin connector and DOES NOT need to be modified. *This info does not
apply to vehicles that utilize IACV solenoids.
The 2 center pins (Black-Red wires) supply 12V power to the stepper motor in the factory setup,
however these pins MUST BE DISCONNECTED before powering on the AEM Infinity ECU.