GM Service Manual Online
For 1990-2009 cars only
  1. Remove the air cleaner intake duct. Refer to Air Cleaner Inlet Duct Replacement .
  2. Fully open the throttle valve in order to Inspect the throttle body bore and the throttle valve plate for any deposits.
  3. Notice: Do not subject a throttle body assembly which contains the following components to an immersion cleaner or a strong solvent:

       • Throttle position (TP) sensor
       • Idle air control (IAC) valve
       • Sealed throttle shaft bearings
    The cleaners will damage the electric components or sensors.

    The cleaners will damage some of these components that contain seals or O-rings.

    Solvents can wash away or break down the grease used on non-serviceable throttle shaft bearings.

    Never use a wire brush or scraper to clean the throttle body. A wire brush or sharp tools may damage the throttle body components.

    Do not use a cleaner that contains methyl ethyl ketone. This extremely strong solvent may damage components and is not necessary for this type of cleaning.

  4. Use a clean shop towel and Top Engine Cleaner GM P/N 1052626 or equivalent product in order to clean the throttle body bore and the throttle valve plate.
  5. If necessary, use a parts cleaning brush in order to remove heavy deposits.

  6. Install the air cleaner duct. Refer to Air Cleaner Inlet Duct Replacement .