Idle Speed/Throttle Actuator - Electronic: Description and Operation

Idle Air Control Valve 20V:

The Idle Air Control Valve is located on the left side of the engine next to the throttle body.

The idle air control valve regulates the volume of air that by-passes the throttle plate. A by-pass air hose is branched off the air intake hose ahead of the throttle plate. By-pass air is routed through the idle air control valve and into the rear of the intake manifold.

A pulsed ground (duty cycle) from the Motronic control module regulates the opening of the idle air control valve. The duty cycle can range anywhere from 25% to 95%.

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.