Idle Air Control (IAC) Valve Replacement

REMOVAL PROCEDURE




1. Disconnect the Idle Air Control (IAC) valve harness connector.




2. Remove the IAC valve attaching screws.

NOTE:If the IAC valve has been in service: DO NOT push or pull on the IAC valve pintle. The force required to move the pintle may damage the threads on the worm drive. Also, DO NOT soak the IAC valve in any liquid cleaner or solvent, as damage may result.




3. Remove the IAC valve and O-ring seal from the throttle body assembly.

Cleaning and Inspection Procedure

1. Clean the IAC valve using GM cleaner 1052626, GM X-66A, or the equivalent. Do not use a solvent containing an extremely powerful solvent such as methyl ethyl ketone. Use a shop towel or parts brush to remove heavy deposits.
2. Shiny spots on the pintle or seat are normal and do not indicate misalignment or a bent pintle shaft.
3. Inspect the IAC valve O-ring for cuts, cracks, or distortion. Replace the O-ring if it is damaged.
4. Clean the IAC valve O-ring sealing surface, the pintle valve seat, and the air passage.
5. Remove the throttle body for a complete cleaning if the air passage has heavy deposits.

INSTALLATION PROCEDURE

IMPORTANT: Use an identical part when installing a new IAC valve. The IAC valve pintle shape and dimensions are designed for specific applications.




1. Measure the distance between the IAC valve pintle and mounting flange. Use finger pressure to slowly retract the pintle if the distance is more than 28 mm (1.1 in.).




2. Lubricate the IAC valve O-ring with clean engine oil.
3. Install the IAC valve O-ring on the IAC valve.
4. Install the IAC valve.
5. Align the IAC valve flange holes with the throttle body attaching screw holes.

NOTE: Refer to Fastener Notice in Cautions and Notices.




6. Install the IAC valve attaching screws.

Tighten
Tighten the IAC valve attaching screws to 3.1 N.m (26 lb in.).




7. Connect the IAC valve harness connector.
8. Reset the IAC valve pintle position.