Idle Speed/Throttle Actuator - Electronic: Description and Operation

Idle Air Control (IAC) Valve:

PURPOSE
The Idle Air Control (IAC) Valve changes the amount of air bypassing the throttle body in response to a signal from the Engine Control Module (ECM) in order to maintain the proper idle speed.

OPERATION
Electrical current applied to the terminals of the IAC valve causes the electromagnet inside to pull the shaft back and open the valve, allowing air to bypass the throttle body.

CONSTRUCTION
Consists of a cast aluminum housing containing an electromagnetically controlled valve.