Idle Up Control Valve: Description and Operation

PURPOSE
The Idle Air Control (IAC) solenoid regulates idle speed by adjusting the amount of air allowed into the intake manifold.

OPERATION
Adjustment is made by varying the duty cycle output of the Powertrain Control Module (PCM). The PCM will increase the duty cycle for added mechanical or electrical loads.
The IAC solenoid is combined with the Fast Idle Control (FIC) solenoid which is turned on when the air conditioner is engaged to help compensate for the additional load.

NOTE: The IAC valve must be replaced as an assembly with the FIC solenoid.