Removal Procedure
- Relieve the high side fuel system pressure. Refer to 
Fuel Pressure Relief.
 
- Disconnect the engine wiring harness electrical connector (1) from the fuel injector wiring harness electrical connector.
 
- Remove the intake manifold. Refer to 
Intake Manifold Replacement.
 
- Remove the fuel injector insulator.
 
- Disconnect the engine wiring harness electrical connector (1) from the
high pressure fuel pump.
 
- Remove the intermediate fuel pipe. Refer to 
Fuel Feed Intermediate Pipe Replacement.
 
- Disconnect the fuel injector wiring harness electrical connectors from the fuel injectors.
 
- 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.
- Carefully remove the fuel rail (2).
 
- If the fuel injectors have been removed with the fuel rail, reinstall the injectors. Refer to 
Direct Fuel Injector Replacement.
 
- Remove and discard the fuel injector upper O-ring seal (1).
 
- 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.
- If replacing the fuel rail, remove the fuel injection fuel rail fuel pressure sensor.
 
- Remove the fuel injector wiring harness.
 
Installation Procedure
- 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.
 
-  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 in the Preface section.
- Install the fuel injection fuel rail fuel pressure sensor.
 
Tighten
Tighten the sensor to 33 N·m (25 lb ft).
- Install the fuel injector wiring harness.
 
- Install a NEW plastic spacer (2) if the old one was damaged.
 
- 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.
 
- Install the NEW fuel injector upper O-ring seal (1).
 
- Place the fuel rail (2) into position.
 
- Install the 2 outer fuel rail bolts (1) first hand tight, and then install the remaining 2 bolts, hand tight.
 
- Connect the fuel injector wiring harness electrical connectors to the fuel injectors.
 
- Tighten the fuel rail bolts in the
sequence shown.
 
Tighten
|     •  | 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). | 
 
- Install the intermediate fuel pipe. Refer to 
Fuel Feed Intermediate Pipe Replacement.
 
- Connect the engine wiring harness electrical connector (1) to the high
pressure fuel pump.
 
- Install the fuel injector insulator.
 
- Install the intake manifold. Refer to 
Intake Manifold Replacement.
 
- Connect the engine wiring harness electrical connector (1) to the fuel injector wiring harness electrical
connector.
 
- Inspect for leaks using the following procedure:
 
| 17.1.  | Turn ON the ignition, with the engine OFF for 2 seconds. | 
 
| 17.2.  | Turn OFF the ignition, for 10 seconds. | 
 
| 17.3.  | Turn ON the ignition, with the engine OFF. | 
 
| 17.4.  | Inspect for fuel leaks. | 
 
- Install the low side fuel pressure service port cap.
 
- Tighten the fuel fill cap.
 
- Install the air cleaner assembly. Refer to 
Air Cleaner Assembly Replacement.