Idle Speed/Throttle Actuator - Electronic: Description and Operation

Idle Air Flow.:

Idle Air Control Wiring.:

Idle Air Control Valve.:

PURPOSE
The Idle Air Control (IAC) valve is used to control engine speed by controlling the amount of airflow around the throttle valve. The PCM does this by moving the IAC pintle in and out.


CIRCUIT OPERATION
The PCM controls engine idle speed by controlling current to two stepper coils contained within the idle air control valve assembly.

By controlling current to both of the coils, the PCM can control engine idle speed by allowing air to bypass around the throttle plate.


LOCATION
The IAC valve is located on the Throttle Body.