Diesel Data: Automotive Repair

Idle Speed/Throttle Actuator - Electronic: Description and Operation

IACV-Auxiliary Air Control Valve:





PURPOSE
Controls engine idle speed during closed loop operation.


OPERATION
It receives a pulse signal from the Engine Control Module (ECU) which opens and closes an air passage allowing a precise amount of air to flow through the valve. Longer pulses allow greater amounts of air which increase idle speed.