Operation CHARM: Car repair manuals for everyone.

Idle Up Control Valve: Description and Operation






Purpose and Operation

The Idle Air Control (IAC) valve:

^ is used to control engine idle speed (rpm).

Idle Air Control (IAC) Valve:






^ is mounted on the throttle body, upper intake manifold or the throttle body adapter (depending upon application).

^ allows air to bypass the throttle plate. The amount of air allowed to bypass is determined by the powertrain control module (PCM) and controlled by a duty cycle signal.