GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

  1. Turn OFF the ignition.

  2. Object Number: 289014  Size: SH
  3. Remove the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical.

  4. Object Number: 290670  Size: SH
  5. Remove the electrical harness (4) from the idle air control (IAC) valve (1).
  6. Remove the exhaust gas recirculation (EGR) valve. Refer to Exhaust Gas Recirculation Valve Replacement .

  7. Object Number: 255249  Size: SH
  8. Remove the IAC valve attaching screws (3) from the IAC valve (2).
  9. Remove the IAC valve (2) from the throttle body.
  10. Remove the O-ring from the IAC valve.

Installation Procedure

Notice: The IAC valve may be damaged if installed with the cone (pintle) extended more than 28 mm (1-1/8 in). Measure the distance that the valve is extended before installing a new valve. The distance from the idle air control valve motor housing to the end of the idle air control valve pintle should be less than 28 mm (1-1/8 in). Manually compress the pintle until the extension is less than 28 mm (1-1/8 in).

  1. Install the new idle air control O-ring on the IAC valve.

  2. Object Number: 255249  Size: SH
  3. Install the IAC valve (2) into the throttle body.
  4. 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.

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


    Object Number: 290670  Size: SH
  7. Connect the electrical harness (4) to the IAC valve (1).
  8. Install the EGR valve. Refer to Exhaust Gas Recirculation Valve Replacement .
  9. Important: The powertrain control module (PCM) will reset the IAC valve whenever the ignition switch is turned ON, then OFF.

  10. Turn ON the ignition, with the engine OFF.
  11. Turn OFF the ignition for 5 seconds.
  12. Start the engine. Allow the engine to reach a normal operating temperature. Inspect for proper operation.

  13. Object Number: 289014  Size: SH
  14. Install the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical.