Fleetwood V8-5.7L VIN P (1994)
Idle Speed/Throttle Actuator - Electronic: Description and Operation
Idle Air Control (IAC) Valve Circuit
PURPOSE
The Idle Air Control Valve (IAC) valve controls the engine idle speed, while preventing stalls due to changes in engine load.
OPERATION
The IAC controls the amount of air bypassed around the throttle plate. This is actually a controlled vacuum leak. When more air is bypassed, idle
speed increases, when less air is bypassed, the idle speed decreases. The IAC valve accomplishes this by moving a conical shaped pintle "IN" to
decrease bypassed air and "OUT" to increase bypassed air. This can be seen as counts displayed on a "Scan" tool. Inward Movement of the pintle =
Decreased RPM = Lower Counts. Outward Movement of the pintle = Increased RPM = Higher Counts.
