GM Service Manual Online
For 1990-2009 cars only
  1. Remove the air cleaner outlet duct. Refer to Air Cleaner Outlet Duct Replacement .
  2. Warning: Turn OFF the ignition before inserting fingers into the throttle bore. Unexpected movement of the throttle blade could cause personal injury.

    Caution: Do not insert any tools into the throttle body bore in order to avoid damage to the throttle valve plate.

  3. Inspect the throttle body bore and the throttle plate for deposits. You will need to open the throttle plate in order to inspect all surfaces.
  4. Caution: Do not use any solvent that contains Methyl Ethyl Ketone (MEK). This solvent may damage fuel system components.

  5. Clean the throttle body bore and the throttle 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 an equivalent product.
  6. Install the air cleaner outlet duct. Refer to Air Cleaner Outlet Duct Replacement .