AEM 30-71XX Infinity Stand-Alone Programmable Engine Mangement System Full Manual - Manual (Page 127)

Tuning Guide 121
© 2014 AEM Performance Electronics
Idle Setup: Stepper Idle Valves
(For 2-wire PWM idle valves, or drive-by-wire vehicles, please skip ahead to the Idle Basic
Setup section.)
When working with a 4-wire or 6-wire stepper idle valve, it is necessary for the ECU to know the
correct value for Idle Stepper max steps before adjusting any other idle settings. The ECU can
never measure a stepper valve's actual position, it can only command that the valve take steps
up or steps down and remember how many steps have been commanded. To operate a stepper
valve correctly, the ECU must know the maximum number of steps that can be commanded
before hitting the mechanical stop. Please follow the instructions below to determine the correct
value for Idle Stepper Max Steps on an unknown idle stepper motor.
1. With the engine off, remove accessory components as needed so the stepper valve's
plunger is visible and it is possible to hear the sound of the stepper valve hitting its
mechanical stop. Note that some setups use the engine's intake manifold or throttle body
for the mechanical stop; when working with these setups, the stepper valve must remain
connected to the mechanical stop.
2. Without changing the Idle Max Position, disable feedback by setting the Idle Feedback
Min and Idle Feedback Max to 0%.
3. Set the IdleBasePosition to zero.
4. Press [CTRL+U] to increase the IdleBasePosition value one percent at a time, from 0 to
100. If you hear the idle valve hit the mechanical stop before the table value is 100 , your
Idle Max Position is too high. If you do not hear the idle valve hit the mechanical stop,
the Idle Max Position may be too low.
5. Increase the Idle Max Position value by one.
6. Reset the ECU (so it will park the idle valve).
7. Repeat the test again. The goal is to use most of the stepper’s possible range without
letting the valve hit the stop.
Idle Basic Setup:
The next step before tuning the idle system is to determine the direction of the motor. The ECU
displays the channel Idle Position, which is 0–100 percent. For some vehicles, increasing the
Idle Position will decrease the airflow to the engine, and it's important for the ECU to be aware
if this is the case. It is very easy to determine which way your specific idle valve works.
1. Open Infinity Tuner and connect to the ECU.
2. Confirm the Throttle is set properly and the ECU's Throttle channel increases from 0% as
soon as the throttle is pressed without any 'dead spots'.
3. Open the Idle Wizard and set Idle On Below TPS to 10%.
4. Initially set the Idle On Below RPM to 3000RPM.
5. Set the option Idle Feedback Min to -50%, and Idle Feedback Max to 50%.
6. Open the Idle Tab and set the entire IdleTargetTable to 2000 RPM.
7. Temporarily set the entire IdleBasePosition table to 50.