Throttle Body Assembly Removal and Replacement

Throttle Position Sensor Electrical Connector:

Air Inlet Duct Fastener:

SERVICE INFORMATION
The throttle body assembly repair procedures cover component replacement with the unit on the vehicle. However, the throttle body replacement requires that the complete unit be removed from the engine. An 8 digit part identification number is stamped on the bottom of the throttle body casting. Refer to this number if servicing, or part replacement is required.

While on-vehicle or off, clean the throttle bore and valve deposits using the carburetor cleaner and a parts cleaning brush. Follow the instructions on container.

THREAD LOCKING COMPOUND

WARNING: In precoating screws, do not use a higher strength locking compound than recommended. Doing so could make removing the screw extremely difficult or result in damaging the screw head.

The service repair kits are supplied with a small vial of thread-locking compound with directions for use. If the material is not available, use Loctite 262 or the equivalent.

Do not use a cleaner that contains methyl ethyl ketone, an extremely strong solvent, and not necessary for this type of deposit.

The throttle body metal parts may be cleaned following the disassembly in a cold immersion-type cleaner such as GM X-55 or the equivalent.

WARNING: Do not immerse the Throttle Position (TP) sensor and Idle Air Control (IAC) valve in any type of cleaner because they are electronic devices.

REMOVAL PROCEDURE
1. Disconnect the negative battery cable.
2. Remove the air inlet duct fastener and the duct.
3. Remove the IAC valve and the TP sensor electrical connectors.
4. Remove the throttle and cruise control cables.
5. Remove the accelerator cable bracket nuts and the bracket.
6. Remove the throttle body retaining bolts or studs.
7. Remove the throttle body assembly.
8. Remove the flange gasket.
9. Discard the flange gasket.

INSTALLATION PROCEDURE

WARNING: In order to prevent damage to the sealing surfaces, carefully use sharp tools in cleaning the old gasket from the aluminum surfaces.

1. Clean the gasket surface on the intake manifold.
2. Install a new flange gasket.
3. Install the throttle body assembly.
4. Install the throttle body assembly retaining bolt or stud.

Tighten
- Tighten the throttle body attaching bolt or stud to 25 Nm (18 lb. in.).

NOTE: Make sure the throttle and cruise control linkage does not hold the throttle open. Refer to Accelerator Controls. Service and Repair

5. Install the throttle and cruise control cables.
6. Install the accelerator cable bracket.
7. install the accelerator cable bracket nuts.
8. Install the IAC valve electrical connector.
9. Install the TP sensor electrical connector.
10. Install the air inlet duct and retaining nut.

Tighten
- Tighten the nut to 2.5 Nm (22 lb. in.).

11. Connect the negative battery cable.
12. With the engine off, check to see that the accelerator pedal is free.

12.1. Depress the pedal to the floor.
12.2. Release the accelerator pedal.

CONTROLLED IDLE SPEED
There should be no DTCs displayed. The idle air control system has been checked.

1. Set the parking brake.
2. Block the drive wheels.
3. Connect a scan tool to the Data Link Connector (DLC) with the tool in the open mode.
4. Start the engine.
5. Bring the engine to the normal operating temperature.
6. Check for the correct state of PRNDL (R-D-L) switch position on the scan tool.
7. Check the specifications table for controlled idle speed and IAC valve pintle position (counts). Refer to Specifications. Service and Repair

8. If within specifications, the idle speed is being correctly controlled by the control module.
9. If not within specifications, refer to Symptoms. Testing and Inspection