GM Service Manual Online
For 1990-2009 cars only
  1. Remove the air cleaner outlet duct. Refer to Air Cleaner Outlet Duct Replacement .
  2. Inspect the throttle body bore and the throttle valve plate for deposits. It is necessary to open the throttle valve to inspect all surfaces.
  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. Clean the throttle body bore and the throttle valve plate using a clean shop towel with GM Top Engine Cleaner, P/N 1052626 or AC-Delco Carburetor Tune-Up Conditioner, P/N X66-P, or equivalent product.
  5. Remove and disassemble the throttle body for cleaning if the deposits are excessive. Refer to the following procedures:
  6. •  Throttle Body Assembly Replacement
    •  Throttle Position Sensor Replacement
    •  Idle Air Control Valve Replacement
  7. After disassembly, clean the throttle body using a parts cleaning brush. DO NOT immerse the throttle body in any cleaning solvent.
  8. Assemble and install the throttle body if previously done. Refer to the following procedures:
  9. •  Throttle Body Assembly Replacement
    •  Throttle Position Sensor Replacement
    •  Idle Air Control Valve Replacement
  10. Install the air cleaner outlet duct. Refer to Air Cleaner Outlet Duct Replacement .