Throttle Body: Service and Repair

Throttle Body And Intake Exploded View:

REMOVAL:

1. Relieve fuel system pressure. Refer to MAINTENANCE PROCEDURES/FUEL SYSTEM PRESSURE RELIEF.
2. Disconnect the negative battery terminal.
3. Drain engine coolant.
4. Remove air cleaner and air box assembly.
5. Disconnect the accelerator cable.
6. Disconnect kick-down cable if equipped.
7. Disconnect the cruise control cable if equipped.
8. Disconnect the two electrical connectors.
9. Disconnect coolant hose from air valve.
10. Disconnect all vacuum hoses.
11. Remove the fuel pressure line and clamp hold down to throttle body.
12. Disconnect the fuel return line at the pressure regulator.
13. Remove the four fasteners holding the throttle body to the intake manifold.
14. Disconnect the PCV hose at the throttle body.
15. Remove the throttle body from intake manifold.

DISASSEMBLY:

NOTE:

a. Be sure to replace gaskets and o-rings as well as worn or damaged parts.
b. While disassembling and assembling the throttle body, use special care NOT to deform levers on the throttle valve shaft or cause damage to any other parts.

Throttle Body Top View:

Checking Passages:

1. Remove the fuel injector. Refer to FUEL INJECTOR ASSEMBLY.
2. Remove the throttle position sensor. Refer to THROTTLE POSITION SENSOR (TPS).
3. Remove the fuel pressure regulator. Refer to PRESSURE REGULATOR ASSEMBLY.
4. Remove the ISC solenoid valve. Refer to IDLE SPEED CONTROL VALVE (ISC).
5. After removing the screws, separate the upper and lower bodies.
6. Clean all passages and fuel injector chamber by blowing it out with compressed air.

NOTE:

a. The throttle position sensor, ISC solenoid valve, fuel injector, fuel pressure regulator, air valve, throttle opener and other components containing rubber must NOT be placed in any solvent or cleaner bath. A chemical reaction will cause these parts to swell, harden, or deform.
b. DO NOT put drills or wires into the passages for cleaning. They will damage the passages.

ASSEMBLY:

1. Install a new gasket to the lower body assembly.
2. Install the upper body on the gasket, using care not to cause to gasket to slip out of place.
3. Install the ISC solenoid valve. Refer to IDLE SPEED CONTROL VALVE (ISC).
4. Install the fuel pressure regulator. Refer to PRESSURE REGULATOR ASSEMBLY.
5. Install the TPS. Refer to THROTTLE POSITION SENSOR (TPS).
6. Install the fuel injector. Refer to FUEL INJECTOR ASSEMBLY.

INSTALLATION:

1. Install a new throttle body base gasket.
2. Install the throttle body to the intake manifold.
3. Install the four fasteners. Tighten to 18.0 to 28.0 N-m (13.0 to 20.0 lb. ft.).
4. Reconnect the PCV hose to the throttle body.
5. Reconnect the fuel pressure line and clamp.
6. Reconnect the fuel return line.
7. Reconnect all vacuum hoses.
8. Reconnect the two electrical connectors.
9. Reconnect the engine coolant hose to the air valve.
10. Reconnect the accelerator cable and adjust. Refer to ADJUSTMENT PROCEDURES/ACCELERATOR CONTROLS.
11. Reconnect the cruise control cable if equipped.
12. Reconnect the kick-down cable if equipped. Refer to ADJUSTMENT PROCEDURES/ACCELERATOR CONTROLS.
13. Refill coolant to the proper level.
14. Reconnect the negative battery terminal.
15. START engine and check for fuel leaks.