Lumina L4-151 2.5L (1991)
Idle Speed/Throttle Actuator - Electronic: Testing and Inspection
Idle Air Control (IAC) Reset Procedure
To reset the Idle Air Control (IAC) valve pintle position, proceed with the following:
1.
Block the drive wheels, and apply the parking brake. Select "Engine rpm" on "Scan" tool.
2.
Start the engine, and hold the engine speed above 2000 rpm. Select "Field Service Mode" for ten seconds (this will reset the IAC valve pintle
position).
3.
Exit "Field Service Mode," and allow the engine to return to idle.
4.
Turn the ignition "OFF," then restart the engine and check for the proper idle operation.