Idle Speed/Throttle Actuator - Electronic: Description and Operation

PURPOSE
To control idle speed during various engine operating conditions such as operating temperature and loads.

Idle Air Control Valve - Auxiliary Air Control Valve:

OPERATION
The Idle Air Control Valve-Auxiliary Air Control (IACV-AAC) Valve is mounted in the IACV unit housing.
The IACV-AAC Valve compensates for changes in idle speed caused by variances in engine load and temperatures.
The IACV-AAC Valve is actuated by the Engine Control Module (ECM) with an ON/OFF pulse, or "Duty Cycle".
The longer the ON Duty is activated the more air will flow through the valve assembly.

< Increased Air Flow >
Raises idle speed.

> Decreased Air Flow <
Lowers idle speed.

Idle Air Control Valve (IACV) Unit Components:

CONSTRUCTION
The IACV-AAC Valve is mounted as a sub-component of the IACV unit housing.