Fuel Injector: Service and Repair

REMOVAL

Fuel Injector:

1. Release fuel pressure from fuel system.
2. Carefully remove electrical harness connectors from individual injectors.
3. Disconnect throttle linkage at throttle ball. Disconnect AOD transmission linkage from throttle body. Remove two bolts securing throttle linkage bracket to intake. Position bracket with cables out of way.
CAUTION: When disconnecting throttle cable from ball stud and pry slowly. Pulling by hand may damage the cable.
4. Disconnect upper intake manifold vacuum fitting connections by disconnecting all vacuum lines to vacuum tree, vacuum lines to EGR valve, and vacuum line to fuel pressure regulator.
5. Disconnect PCV system by disconnecting hose from fitting on rear of upper manifold.
6. Remove canister purge line(s) from fitting(s) on throttle body.
7. Disconnect water heater lines from the throttle body.
8. Disconnect EGR tube from EGR valve by removing flange nut.
9. Remove bolt from upper intake support bracket to upper manifold.
10. Remove six upper intake manifold retaining bolts.
11. Remove upper intake and throttle body as an assembly from lower intake manifold.

Fuel Injector:

12. Grasping injector body, pull up while gently rocking injector from side to side.

Fuel Injector:

13. Inspect injector rings (two per injector) for signs of deterioration. Replace as needed.
CAUTION: Do not attempt to clean the injector pintle or metering orifice with tools or brushes.

INSTALLATION


1. Lubricate new O-rings with a light grade oil and install two on each injector.
CAUTION: Never use silicone grease. It will clog the injectors.
2. Install injector(s) using light, twisting, pushing motion.
3. Secure the fuel supply manifold assembly using four retaining bolts. Tighten to 87 lb. in. (10 N-m).
4. Connect the fuel inlet and outlet lines at the fuel rail connections. Push in to connect. Connect fuel line retaining clips.
5. Position new gasket on lower intake mounting face. The use of alignment studs may be helpful.
6. Install electrical harness connectors to injectors.
7. Install upper intake manifold and throttle body assembly to lower manifold making sure gasket remains in place (if alignment studs aren't used).
8. Install six upper intake manifold retaining bolts and tighten to 24 lb. ft. (32 N-m).
9. Install upper intake support bracket to upper manifold attaching bolt.
10. Install EGR tube.
11. Install canister purge lines to fittings on throttle body.
12. Connect water heater lines to the throttle body.
13. Connect PCV hose to rear of upper manifold.
14. Connect vacuum lines to vacuum tree, EGR valve, and fuel pressure regulator.
15. Position throttle linkage bracket with cables to upper intake manifold. Install two attaching bolts and tighten TO 13 lb. ft. (17 N-m). Connect throttle cable and transmission cable to throttle body.
16. Connect electrical connectors at air bypass valve, TP sensor, and EGR position sensor.