Throttle Body: Service and Repair

Throttle Body Components:

REMOVAL PROCEDURE
1. Disconnect the negative battery cable.
2. Partially drain the cooling system in order to remove the hoses at the throttle body.
3. Disconnect the distributor ventilation vacuum line from the air intake duct.
4. Disconnect the IAT sensor (2) and MAF sensor (1) electrical connectors.
5. Remove the air intake duct with the air cleaner top.
6. Disconnect the TP sensor (2) and AC valve (1) electrical connectors.
7. Disconnect the accelerator control cable and the cruise control cable from the throttle body.
8. Disconnect the crankcase ventilation hoses from the throttle body.
9. Disconnect the canister purge tube from the throttle body.
10. Disconnect the coolant hoses from the throttle body.
11. Remove the throttle body attaching bolts.
12. Remove the throttle body and the gasket. Discard the gasket.

CAUTION:
^ In order to prevent damage to the sealing surfaces, carefully use sharp tools in cleaning the old gasket from the aluminum surfaces.
^ Do Not soak the throttle body in cold immersion type cleaner. The throttle valve has a factory applied sealing compound (DAG material is applied to the outside edge of the 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.

13. Clean the gasket sealing surfaces.

INSTALLATION PROCEDURE
1. Install the throttle body with a new gasket.
2. Install the throttle body attaching bolts.

Tighten
Bolts to 12 Nm (106 lb in).

3. Connect the coolant hoses to the throttle body.
4. Connect the canister purge tube to the throttle body.
5. Connect the crankcase ventilation hoses to the throttle body.
6. Connect the accelerator control cable and the cruise control cable.
7. Connect the TP sensor (2) and the IAC valve (1) electrical connectors.
8. Install the air intake duct with the air cleaner top.
9. Connect the IAT sensor (2) and MAF sensor (1) electrical connectors.
10. Refill the cooling system.
11. Connect the negative battery cable.
12. With the engine OFF, check to see that the accelerator pedal is free. Depress the accelerator pedal to the floor and release.
13. Reset the IAC valve pintle position.
A. Depress the accelerator pedal slightly.
B. Start the engine.
C. Release the accelerator pedal.
D. Run the engine for 5 seconds.
E Turn the ignition OFF for 10 seconds.
F. Restart the engine.
G. Check for proper idle operation.