GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 1999 🢒 GMC K Sierra - 4WD 🢒 Engine 🢒 Engine Controls - 4.8L, 5.3L, and 6.0L 🢒 Idle Air Control Valve Replacement

Removal Procedure

    Object Number: 389028 Size: SH
  1. Disconnect the IAC valve electrical connector.

    2. Object Number: 356448 Size: SH
  2. Remove the IAC valve attaching screws (4).
  3. Remove the IAC valve (3).
  4. Remove the IAC valve O-ring seal (2).

    5. Notice: 

       • Do Not push or pull on the IAC valve pintle on IAC valves that have been in service. The force required to move the pintle may damage the threads on the worm drive.
       • Do Not soak the IAC valve in any liquid cleaner or solvent, as damage may result.

  5. Clean the IAC valve O-ring sealing surface, the pintle valve seat, and the air passage.
    6. • Clean the IAC valve using GM cleaner 1052626 or GM X-66A. Use a shop towel or parts brush to remove heavy deposits.
    • If the air passage has heavy deposits, remove the throttle body for complete cleaning.
    • Shiny spots on the pintle or seat are normal, and do not indicate misalignment or a bent pintle shaft.
  6. Inspect the IAC valve O-ring for cuts, cracks, or distortion. Replace the O-ring if it is damaged.

Installation Procedure

    Object Number: 17065 Size: SH

    Important: If installing a new IAC valve, be sure to replace it with an identical part. The pintle shape of the IAC valve and the diameter of the IAC valve are designed for the specific application.

  1. Measure the distance between the tip of the IAC valve pintle and the mounting surface (1). If the distance is greater than 28 mm (1.1 in), use finger pressure to slowly retract the pintle. The force required to retract the pintle of a new valve will not cause damage to the valve.

    2. Object Number: 356448 Size: SH
  2. Lubricate the IAC valve O-ring (2) with clean engine oil.
  3. Install the IAC valve O-ring (2) on the IAC valve (3).
  4. Install the IAC valve (3).
  5. Apply Loctite 262 to the IAC valve attaching screw threads if necessary.

    6. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  6. Install the IAC valve attaching screws (4).

    7. Tighten
    Tighten the IAC valve attaching screws to 3 N·m (27 lb in).


    Object Number: 389028 Size: SH
  7. Connect the IAC valve electrical connector.
  8. Perform the Idle Learn Procedure. Refer to PCM Idle Learn Procedure .