Fuel Pump Replacement LLT

Special Tools

EN-48896 High Pressure Fuel Pump Installation Alignment Gage

1. Relieve the low and high side fuel system pressure. Refer to Fuel Pressure Relief .
2. Remove the high pressure fuel pump shield. Refer to Fuel Pipe Shield Replacement .
3. Remove the intake manifold. Refer to Intake Manifold Replacement .



4. Disconnect the engine wiring harness electrical connector from the high pressure fuel pump.
5. Remove the low pressure feed pipe. Refer to Fuel Feed Pipe Replacement .
6. Remove the high pressure pipe. Refer to Fuel Feed Intermediate Pipe Replacement . Discard this pipe.
7. Remove and discard the high pressure fuel pump bolts (4).
8. Remove the high pressure fuel pump (3).
9. Remove and discard the high pressure fuel pump gasket (2).
10. Remove and discard the high pressure fuel pump O-ring.
11. Remove the high pressure fuel pump roller lifter.

Note: The camshaft must be in the base circle position before the high pressure fuel pump is installed.

1. Use the EN-48896 alignment gage to ensure that the camshaft lobe is in the base circle position. At base circle the tool will be flush with the head.
2. Lubricate the high pressure fuel pump cylinder head bore and roller lifter with camshaft prelube GM P/N 12345501 (Canadian P/N 992704) or equivalent.
3. Install high pressure fuel pump roller lifter.
4. Install a NEW high pressure fuel pump O-ring.




Note: The high pressure fuel pump gasket has a retaining feature to hold the pump retaining bolts in place.

5. Position the NEW high pressure fuel pump gasket (2) and bolts (4) to the fuel pump.
6. Install the high pressure fuel pump (3) to the cylinder head (1). Force will be required while hand tightening the bolts.

Caution: Refer to Fastener Caution in the Preface section.

7. Tighten the high pressure fuel pump retaining bolts to 15 N·m (11 lb ft) .
8. Ensure the high pressure fuel pump and fuel rail fittings are clean prior to assembly.
9. Install a NEW high pressure fuel pipe. Refer to Fuel Feed Intermediate Pipe Replacement .
10. Install the fuel feed pipe to the high pressure fuel pump. Refer to Fuel Feed Pipe Replacement .
11. Connect the high pressure fuel pump wiring harness.
12. Install the fuel tank cap.

Note: If a fuel leak accrues at the fuel rail, the fuel rail will need to be replaced.

13. Inspect for leaks using the following procedure:

13.1.

Turn ON the ignition, with the engine OFF for 2 seconds.

13.2.

Turn OFF the ignition, for 10 seconds.

13.3.

Turn ON the ignition, with the engine OFF.

13.4.

Inspect for fuel leaks.

14. Install the pressure relief cap to the fuel feed pipe.
15. Install the intake manifold. Refer to Intake Manifold Replacement .
16. Install the high pressure fuel pump shield. Refer to Fuel Pipe Shield Replacement .