Fuel Rail: Service and Repair

Fuel Injection Fuel Rail Assembly Replacement

Removal Procedure





1. Disconnect the engine wiring harness electrical connector (1) from the fuel injector wiring harness electrical connector.
2. Remove the intake manifold. Refer to Intake Manifold Replacement (Service and Repair) .




3. Remove the fuel injector insulator.




4. Relieve the high side fuel system pressure. Refer to Fuel Pressure Relief (Low Pressure Side with CH 48207) (Fuel Pressure Relief (Low Pressure Side with CH 48207))Fuel Pressure Relief (Low Pressure Side with CH 48027-100) (Fuel Pressure Relief (Low Pressure Side with CH 48027-100))Fuel Pressure Relief (Low Pressure Side w/o CH 48207) (Fuel Pressure Relief (Low Pressure Side w/o CH 48207))Fuel Pressure Relief (Low Pressure Side w/o CH 48027-100) (Fuel Pressure Relief (Low Pressure Side w/o CH 48027-100))Fuel Pressure Relief (High Pressure Side) (Fuel Pressure Relief (High Pressure Side)) .
5. Disconnect the engine wiring harness electrical connector (1) from the high pressure fuel pump.




6. Remove the high pressure fuel pump cover bolts.
7. Remove the high pressure fuel pump cover.
8. Remove the engine wiring harness clip from the high pressure fuel pump cover.




9. Remove the high pressure fuel pump insulator.




10. Loosen the high pressure fuel pipe fitting at the fuel pump.
11. Loosen the high pressure fuel pipe fitting at the fuel rail.
12. Remove and discard the high pressure fuel pipe.




13. Disconnect the fuel injector wiring harness electrical connectors from the fuel injectors.
14. Remove the fuel rail bolts (1).

Important: Carefully remove the fuel rail. The fuel injectors may come out of the cylinder head with the fuel rail.


15. Carefully remove the fuel rail (2).
16. If the fuel injectors have been removed with the fuel rail, reinstall the injectors. Refer to Direct Fuel Injector Replacement (Service and Repair) .




17. Remove and discard the fuel injector upper O-ring seal (1).
18. Inspect the plastic spacer (2) for damage, remove if damaged.





Important: Applying force to the plastic housing of the sensor will destroy the sensor. To tighten or loosen, only apply force to the attached hexagon.


19. If replacing the fuel rail, remove the fuel injection fuel rail fuel pressure sensor.
20. Remove the fuel injector wiring harness.



Installation Procedure





1. If the fuel rail was replaced, Lubricate the threads and sealing cone of the NEW fuel rail with silicon free engine oil GM P/N 12345610 (Canadian P/N 993193) or equivalent.
2. Lubricate the threads and sealing cone of the sensor with silicon free engine oil GM P/N 12345610 (Canadian P/N 993193) or equivalent.
Important: Applying force to the plastic housing of the sensor will destroy the sensor. To tighten or loosen, only apply force to the attached hexagon.




Notice: Refer to Fastener Notice (Fastener Notice) .

3. Install the fuel injection fuel rail fuel pressure sensor.

Tighten the sensor to 33 N.m (25 lb ft).

4. Install the fuel injector wiring harness.




5. Install a NEW plastic spacer (2) if the old one was damaged.
6. Lubricate a NEW fuel injector upper O-ring seal (1) with silicon free engine oil GM P/N 12345610 (Canadian P/N 993193) or equivalent.
7. Install the NEW fuel injector upper O-ring seal (1).




8. Place the fuel rail (2) into position.
9. Install the 2 outer fuel rail bolts (1) first hand tight, and then install the remaining 2 bolts, hand tight.
10. Connect the fuel injector wiring harness electrical connectors to the fuel injectors.




11. Tighten the fuel rail bolts in the sequence shown.

* Tighten the bolts a first pass to 22 N.m (16 lb ft).
* Tighten the bolts a final pass to 22 N.m (16 lb ft).






12. Ensure that the high pressure fuel pump, and fuel rail fittings are clean prior to assembly.
13. Lubricate the high pressure fuel pump, and the fuel rail fittings with silicon free engine oil GM P/N 12345610 (Canadian P/N 993193) or equivalent.
14. Install a NEW high pressure fuel pipe.
15. Tighten the NEW high pressure fuel pipe fitting to the fuel rail hand tight.
16. Tighten the NEW high pressure fuel pipe fitting to the fuel pump hand tight.

Tighten the fittings to 32 N.m (24 lb ft).





17. Install the high pressure fuel pump insulator.




18. Install the engine wiring harness clip to the high pressure fuel pump cover.
19. Install the high pressure fuel pump cover.
20. Install the high pressure fuel pump cover bolts.

Tighten the bolts to 10 N.m (89 lb in).





21. Connect the engine wiring harness electrical connector (1) to the high pressure fuel pump.




22. Install the fuel injector insulator.
23. Install the intake manifold. Refer to Intake Manifold Replacement (Service and Repair) .




24. Connect the engine wiring harness electrical connector (1) to the fuel injector wiring harness electrical connector.
25. Inspect for leaks using the following procedure:

1. Turn ON the ignition, with the engine OFF for 2 seconds.
2. Turn OFF the ignition, for 10 seconds.
3. Turn ON the ignition, with the engine OFF.
4. Inspect for fuel leaks.

26. Install the low side fuel pressure service port cap.
27. Tighten the fuel fill cap.
28. Install the intake manifold cover. Refer to Intake Manifold Cover Replacement (Service and Repair) .