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Idle Up Control Valve: Description and Operation






Purpose
The idle air control (IAC) valve is used to control engine idle speed and dashpot functions.

Location and Operation
The idle air control valve is mounted on the throttle body and allows air to bypass the throttle plate. The amount of air allowed to bypass the throttle plate, will be determined by the PCM and be controlled by a duty cycle signal.

CAUTION: Cleaning the IAC valve is NOT recommended. The use of solvents may damage the IAC valve.