GM Service Manual Online
For 1990-2009 cars only
  1. Remove the air cleaner intake duct. Refer to Air Cleaner Outlet 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. Caution: 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 Outlet Duct Replacement.