Special Tools
|     •  | EN-47909 
 Injector Bore and Sleeve Cleaning Kit | 
 
|     •  | EN-48266 
 Injector Seal Installer and Sizer | 
 
Removal Procedure
- Disconnect the engine wiring harness electrical connector (1) from the fuel injector wiring harness electrical connector.
 
- Remove the intake manifold assembly. Refer to 
Intake Manifold Replacement
.
 
- Remove the fuel injector insulator.
 
- Relieve the high side fuel system pressure. Refer to 
Fuel Pressure Relief
 .
 
- Disconnect the engine wiring harness electrical connector (1) from the high pressure fuel pump.
 
- Remove the engine wiring harness clip (3) from the high pressure fuel pump cover.
 
- Remove the fuel feed intermediate 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).
 
- Remove and discard the direct fuel injector hold down clamps.
 
- Remove the direct fuel injectors.
 
- If necessary, use the 
J 2619-01 
 and the 
J-37281-A 
 in order to remove the direct fuel injector(s).
 
- Remove and discard the upper O-ring seal (1) and plastic spacer (2) from the injector(s).
 
- Carefully remove and discard the lower nylon seal (4) from the injector(s).
 
Installation Procedure
- Install a NEW plastic spacer (2) onto the fuel injector(s).
 
- Lubricate a NEW O-ring seal (1) with silicon free engine oil GM P/N 12345610 (Canadian P/N 993193) or equivalent.
 
- Install the NEW O-ring seal (1) onto the fuel injector(s).
 
- From the 
EN-48266 
 , position the EN 48266-1
to the injector tip.
 
Important: DO NOT lubricate the NEW seal.
- Install a NEW seal onto the EN 48266-1.
 
- Pull the NEW seal by hand over the EN 48266-1 and into the groove in the injector.
 
- Remove the EN 48266-1 from the injector tip.
 
- From the 
EN-48266 
 , install the EN 48266-2
to the injector tip.
 
- Using the EN 48266-2, re-size the seal. Install the EN 48266-2, until it
bottoms out against the injector body, and rotate the EN 48266-2 while applying only moderate force 180 degrees in one direction and then 180 degrees back in the other direction.
 
- Remove the EN 48266-2.
 
- Install the direct fuel injectors to the cylinder head.
 
- Install the NEW direct fuel injector hold down clamps.
 
- Place the fuel rail (2) into position.
 
- Install the 2 outer fuel rail bolts (1) first, hand tight and install the remaining 2 bolts, hand tight.
 
- Connect the fuel injector wiring harness electrical connectors to the fuel injectors.
 
Notice: Refer to Fastener Notice in the Preface section.
- 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 fuel feed intermediate pipe. Refer to 
Fuel Feed Intermediate Pipe Replacement
.
 
- Connect the engine wiring harness electrical connector (1) to the high pressure fuel pump.
 
- Install the engine wiring harness clip (3) to the high pressure fuel pump cover.
 
- Install the fuel injector insulator.
 
- Connect the engine wiring harness electrical connector (1) to the fuel injector wiring harness electrical connector.
 
- Inspect for leaks using the following procedure:
 
| 22.1.  | Turn ON the ignition, with the engine OFF for 2 seconds. | 
 
| 22.2.  | Turn OFF the ignition, for 10 seconds. | 
 
| 22.3.  | Turn ON the ignition, with the engine OFF. | 
 
| 22.4.  | Inspect for fuel leaks. | 
 
- Install the low side fuel pressure service port cap.
 
- Tighten the fuel fill cap.
 
- Install the intake manifold assembly. Refer to 
Intake Manifold Replacement
.