Idle Speed Control System

PURPOSE
The Idle Air Control System allows for precise control of the engine idle during cold, warm and high load conditions.




OPERATION
Idle speed (at all temperatures and conditions) is controlled by fine adjustment of the amount of air allowed to pass through the Idle Air Control Valve (IACV - AAC).

The valve is activated by a duty cycle signal from the Engine Control Module (ECM) at a rate of 100 - 200 Hz.

RPM/Engine Temperature Relationship M/T:

RPM/Engine Temperature Relationship A/T:

The Appropriate engine RPM In relation to engine temperature, should be as shown in the charts