Altima L4-2.4L (KA24DE) (1994)
Auxiliary Air Control (AAC) Valve: 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.