The Idle Air Control (IAC) valve adjusts the engine idle speed. The valve is located on the side of the throttle body. The valve is controlled by a duty cycle signal from the PCM and allows air to bypass the throttle plate in order to maintain the proper idle speed.
Do not attempt to clean the IAC valve. Carburetor tune-up cleaners or any type of solvent cleaners will damage the internal components of the valve.
- Turn the ignition switch to the OFF position.
- Disconnect the wiring harness from the IAC valve.
- Measure the resistance between the terminals of the valve.
Due to the diode in the solenoid, place the ohmmeter positive lead on the emphasis type="medium" VPWR/emphasis terminal and the negative lead on the emphasis type="medium" ISC/emphasis terminal.
- Resistance should be 6-13 ohms.
- If resistance is not within specification, the valve may be faulty.
REMOVAL & INSTALLATION
- Disconnect the negative battery cable.
- Remove the air cleaner inlet tube and the throttle cover, if necessary.
- Disconnnect the wiring harness from the IAC valve.
- Remove the two retaining bolts.
- Remove the IAC valve and discard the old gasket.
- Clean the gasket mating surfaces thoroughly.
- Using a new gasket, position the IAC valve on the throttle body.
- Install and tighten the retaining bolts to 71-106 inch lbs. (8-12 Nm).
- Connect the wiring harness to the IAC valve.
- If removed, install the air cleaner tube and throttle cover.
- Connect the negative battery cable.