GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

    Caution: Refer to Battery Disconnect Caution in the Preface section.


    Object Number: 1256160  Size: SH
  1. Disconnect the negative battery cable.
  2. Remove the air intake resonator.
  3. Disconnect the idle air control (IAC) valve connector.
  4. Notice: 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.

  5. Remove the IAC valve retaining bolts.
  6. Remove the IAC valve.
  7. Notice: Do not use any solvent that contains Methyl Ethyl Ketone (MEK). This solvent may damage fuel system components.

  8. Clean the IAC valve O-ring seal area, the pintle valve seat, and the air passage with a suitable fuel system cleaner.

Installation Procedure


    Object Number: 1256160  Size: SH

    Important: If installing a new IAC valve, be sure to replace it with an identical part. The IAC valve pintle shape and diameter are designed for the specific application. Measure the distance between the tip of the IAC valve pintle and the mounting flange. 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 will not damage the IAC valve. The purpose of the 28 mm (1.1 in) setting is to prevent the IAC pintle from bottoming out on the pintle seat. This 28 mm (1.1 in) setting is also an adequate setting for controlled idle on a restart.

  1. Lubricate a new O-ring with engine oil. Install the new O-ring onto the valve.
  2. Install the IAC valve into the throttle body.
  3. Notice: Refer to Fastener Notice in the Preface section.

  4. Install the IAC valve retaining bolts.
  5. Tighten
    Tighten the idle air control valve retaining bolts to 3 N·m (2 lb in).

  6. Connect the IAC valve connector.
  7. Install the air intake resonator.
  8. Connect the negative battery cable.
  9. Start the engine and check for the proper idle speed.