Fuel Rail and Injectors Cleaning and Inspection (LF3)

Special Tools

• EN 49245  Injector Seal Installer Kit

For equivalent regional tools, refer to Special Tools (LF3)Special Tools (LGX) .

Fig 1: View Of Fuel Rail Wiring Harness
Courtesy of GENERAL MOTORS COMPANY
1. Disconnect and remove the fuel rail wiring harness (1).
Fig 2: Fuel Injector
Courtesy of GENERAL MOTORS COMPANY
2. Taking care not to touch or apply force to the injector tip or electrical connector, remove the fuel injector (1) by pressing down on the retainer lever to release the tab (2) and simultaneously rotating the injector 45 degrees and pulling straight out from the fuel rail.
3. Remove the retainer (3) from the fuel injector and discard.
Fig 3: Fuel Injector Components
Courtesy of GENERAL MOTORS COMPANY
4. Using pliers, remove the fuel injector bushing (3) straight out from injector body. Discard bushing (3). Remove and discard the fuel injector O-ring (1) and plastic spacers (2).
5. Remove and discard the fuel injector seals (4).
Fig 4: Identifying Fuel Pressure Sensor
Courtesy of GENERAL MOTORS COMPANY
NOTE:

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

6. Remove the fuel pressure sensor (1).
NOTE:

Do not soak or submerge the fuel rail or injectors in solvent.

7. Clean the exterior of the fuel rail and injectors with solvent.
Fig 5: Identifying Fuel Rail Inspection Areas
Courtesy of GENERAL MOTORS COMPANY
8. Inspect the fuel rail (1) and components for the following conditions:
   • Damage, debris or restrictions to the fuel rail
   • Damage, debris or restrictions to the fuel ports in the fuel rail
   • Damage to the mounting area for the fuel rail
   • Damage to the fuel rail mounting bolts or mounting bolt grommets/isolators
   • Damage to the threads on the fuel rail feed fitting
   • Damage to the threads in the fuel pressure sensor bore
   • Damage to the fuel pressure sensor connector, threads, or sealing face
Fig 6: Identifying Fuel Pressure Sensor
Courtesy of GENERAL MOTORS COMPANY
NOTE:

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

9. Install the fuel pressure sensor (1).
   NOTE:

   Ensure that the fuel rail threads have been cleaned of any excess fuel or the fuel pressure sensor will NOT seal properly.

   1. Lubricate the threads and the sealing area in the fuel rail with silicon free engine oil. Refer to Adhesives, Fluids, Lubricants, and Sealers (LF3)Adhesives, Fluids, Lubricants, and Sealers (LGX) for recommended lubricant.
   2. Lubricate the threads and the sealing area on the fuel pressure sensor with silicon free engine oil. Refer to Adhesives, Fluids, Lubricants, and Sealers (LF3)Adhesives, Fluids, Lubricants, and Sealers (LGX) for recommended lubricant.
   3. Install the fuel pressure sensor hand tight.
   4. Remove the fuel pressure sensor and re-lubricate.
   CAUTION:

   Refer to Fastener Caution .

   5. Install the fuel pressure sensor and tighten to 33 N.m (25 lb ft).
Fig 7: Identifying Fuel Injector Components
Courtesy of GENERAL MOTORS COMPANY
10. Inspect the fuel injectors for the following conditions:
    • Damage to the fuel injector connector (1)
    • Damage to the fuel inlet cone (2)
    • Damage to the fuel injector body (3)
    • Damage to the fuel injector tip (4)
11. Replace the fuel rail or injector if any damage is found. Do not attempt to repair a fuel rail or injector.
Fig 8: Fuel Injector Bushing
Courtesy of GENERAL MOTORS COMPANY
NOTE:

The fuel injector bushing (1) is to be installed BEFORE O-ring or backup rings are installed.

12. Install NEW fuel injector bushing (1) onto injector body. Bushing should seat with a distinct "snap" sound and feel. Ensure bushing is fully seated.
Fig 9: Injector And Components
Courtesy of GENERAL MOTORS COMPANY
13. Install the NEW white plastic spacer (3) on the fuel injector first.
14. Install the brown plastic spacer (2) second.
15. Lubricate the NEW O-ring (1) with one drop of clean engine oil.
Fig 10: Fuel Injector Wiring Harness Connectors
Courtesy of GENERAL MOTORS COMPANY
CAUTION:

Ensure the fuel injectors are installed in the correct orientation. Improper orientation of the fuel injectors may result in engine misfire and possible engine damage.

16. The right side (bank 1) fuel injector wiring harness connectors (1) should point to the rear of the engine. The left side (bank 2) fuel injector wiring harness connectors (2) should point to the front of the engine.
Fig 11: Injector Retainer
Courtesy of GENERAL MOTORS COMPANY
17. Install NEW retainer (3) onto the fuel injector.
18. Holding the largest diameter/body of the injector only, indicated by arrow in graphic, insert the injector assembly (1) into the fuel rail. Ensure correct orientation of the electrical connector (2).
19. Rotate the fuel injector approximately 45 degrees until the tab on the retainer (4) locks into the notch on the fuel rail.
20. Repeat for remaining injectors until all are installed and retained in fuel rail.
Fig 12: View Of Fuel Rail Wiring Harness
Courtesy of GENERAL MOTORS COMPANY
21. Install the fuel rail wiring harness (1).
Fig 13: Identifying Fuel Injector Tip & Seals
Courtesy of GENERAL MOTORS COMPANY
NOTE:

Do not use any type of lubricant when installing the NEW seals (2) on the fuel injector tip.

22. Install EN 49245-1  long protector (3) onto the fuel injector tip, covering the first recessed area closest to the tip. Place a NEW seal (2) on EN-49245-1  long protector.
23. Using EN-49245-3  pusher (1), install the seal into the second recessed area (4) of the fuel injector.
NOTE:

The EN-49245-4  sizer is two sided, and either direction will size the seal correctly.

24. Compress the seal with your fingers, then resize the seal using the EN-49245-4  sizer (5).
Fig 14: Identifying Fuel Injector Tip & Seals
Courtesy of GENERAL MOTORS COMPANY
NOTE:

Do not use any type of lubricant when installing the NEW seals (2) on the fuel injector tip.

25. Install EN-49245-2  short protector (3) onto the fuel injector tip. Place a NEW seal (2) on EN-49245-2  short protector.
26. Using EN-49245-3  pusher (1), install the seal into the first recessed area (4) of the fuel injector.
NOTE:

The EN-49245-4  sizer is two sided, and either direction will size the seal correctly.

27. Compress the seal with your fingers, then resize the seal using the EN-49245-4  sizer (5).