GM Service Manual Online
For 1990-2009 cars only

Removal Procedure


Object Number: 12654  Size: SH

An eight-digit part identification number (3) is stamped on the throttle body casting. Refer to this number if servicing, or part replacement is required.

A build date is stamped on the throttle body which indicates the day of year (1) and the year (2) that the throttle body was manufactured.


    Object Number: 12592  Size: SH
  1. Disconnect the negative battery cable.
  2. Partially drain the cooling system.
  3. Remove the resonator.
  4. Disconnect the electrical connector from the IAT sensor.
  5. Disconnect the distributor ventilation vacuum line from the air intake duct.
  6. Remove the air intake duct.
  7. Disconnect the electrical connectors from the TP sensor and the IAC valve.
  8. Disconnect the vacuum lines from the throttle body.
  9. Disconnect the coolant hoses from the throttle body.
  10. Disconnect the accelerator control cable and the cruise control cable from the throttle body.
  11. Remove the throttle body attaching bolts.
  12. Remove the throttle body and the gasket. Discard the gasket.
  13. Notice: In order to prevent damage to the sealing surfaces, carefully use sharp tools in cleaning the old gasket from the aluminum surfaces.

    Important: 

       • Do Not soak the throttle body in cold immersion type cleaner. The throttle valves have a factory applied sealing compound (DAG material is applied to the outside edge of each valve and the throttle bore) to prevent air bypass at closed throttle. Strong solvents or brushing will remove the material. To clean the throttle body following disassembly, use a spray type cleaner such as GM X-66A or GM 1052626. Use a shop towel to remove heavy deposits.
       • The TP sensor and the IAC valve are electrical components and should NOT come in contact with solvent or cleaner, as damage may result.

  14. Clean the gasket sealing surfaces.

Installation Procedure


    Object Number: 12592  Size: SH
  1. Install the throttle body with a new gasket.
  2. Install the throttle body attaching bolts.
  3. Tighten
    Tighten the throttle body attaching bolts to 25 N·m (18 lb ft).

  4. Connect the accelerator control cable and the cruise control cable.
  5. Connect the coolant hoses to the throttle body.
  6. Connect the vacuum lines to the throttle body.
  7. Connect the electrical connectors to the TP sensor and the IAC valve.
  8. Install the air intake duct.
  9. Connect the distributor ventilation vacuum line to the air intake duct.
  10. Connect the electrical connector to the IAT sensor.
  11. Install the resonator.
  12. Refill the cooling system.
  13. Connect the negative battery cable.
  14. With the engine OFF, check to see that the accelerator pedal is free. Depress the accelerator pedal to the floor and release.
  15. Reset the IAC valve pintle position.
  16. 14.1. Depress the accelerator pedal slightly.
    14.2. Start the engine.
    14.3. Release the accelerator pedal.
    14.4. Run the engine for 5 seconds.
    14.5. Turn the ignition OFF for 10 seconds.
    14.6. Restart the engine.
    14.7. Check for proper idle operation.