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Idle Speed/Throttle Actuator - Electronic: Description and Operation

PURPOSE
The idle air control valve regulates the volume of air that by-passes the throttle plate.
The idle air control valve is also responsible for the amount of air during starting and deceleration. The idle air control system is adaptive and no adjustments are necessary.

OPERATION
A pulsed ground (duty cycle) from the Engine Control Module regulates the opening of the idle air control valve. The duty cycle can range anywhere from 25% to 95%. By-pass air is routed through the idle air control valve and into the intake manifold.