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Idle Up Control Valve: Description and Operation

Idle Air Control (IAC) Valve:

PURPOSE and OPERATION
The Idle Air Control (IAC) valve:
- is used to control engine idle speed (rpm).
- 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.