Idle Speed/Throttle Actuator - Electronic: Description and Operation

PURPOSE
The idle air control valve (IAC) is used to maintain proper idle speeds during varying conditions.

LOCATION
Mounted to the right side of the intake plenum.

CONSTRUCTION
The valve is a duty-cycle operated air control valve.

OPERATION
The IAC receives a continuous signal the ECM. By varying the ON/OFF time ratio of the signal, the ECM is able to control the size of the air passage through the valve. Air passing through the valve bypasses the throttle which, causes an increase in idle speed.