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For 1990-2009 cars only

Fuel Injector Replacement Left

Tools Required

    • EN-47909 Injector Bore and Sleeve Cleaning Kit
    • J 44639 Fuel Injector Removal Tool

Removal Procedure

  1. Remove the engine cover, if required. Refer to Engine Cover Replacement in Interior Trim.
  2. Important: After removing the charged air cooler duct, cover the turbocharger opening with tape in order to prevent entry of objects.

  3. Remove the air cleaner . Refer to Air Cleaner Replacement .
  4. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  5. Remove the charged air cooler pipe. Refer to Charged Air Cooler Hoses/Pipes Replacement in Engine Mechanical - 6.6L (LLY).
  6. If removing the number 8 fuel injector, perform steps 6-12.
  7. Remove the engine oil fill tube. Refer to Oil Filler Tube Replacement .
  8. Remove the fan from the engine and allow the fan to set in the shroud. Refer to Fan Replacement .
  9. If equipped with a manual transmission, remove the left side transmission mount bracket from the transmission. Refer to Transmission Mount Bracket Replacement in Manual Transmission ZF S6-650.
  10. If equipped with an automatic transmission, remove the left side transmission mount from the transmission. Refer to Transmission Mount Replacement in Automatic Transmission - Allison.
  11. If equipped with an automatic transmission, remove the transmission filler tube. Refer to Transmission Fluid Filler Tube and Seal Replacement .
  12. Remove the left side engine mount. Refer to Engine Mount Bracket Replacement - Left Side in Engine Mechanical - 6.6L (LLY).
  13. Lower/tilt the engine and transmission until the fuel filter almost contacts the frame rail. If more clearance is required, remove the fuel filter. Refer to Fuel Filter Replacement . Maintain engine and transmission support.

  14. Object Number: 674653  Size: SH
  15. Disconnect the engine harness main connectors. Lift up on the latch in order to disconnect the connectors.

  16. Object Number: 1334916  Size: SH
  17. Remove the engine harness main electrical connector bolts.
  18. Remove the main electrical connectors from the bracket.

  19. Object Number: 1334948  Size: SH
  20. Disconnect the barometric sensor electrical connector.
  21. Remove the engine wire harness from the clip.
  22. Remove the main electrical harness bracket screws.
  23. Remove the main electrical harness bracket.

  24. Object Number: 1335531  Size: SH
  25. Disconnect the glow plug controller electrical connectors.

  26. Object Number: 1335454  Size: SH
  27. Reposition the left positive crankcase ventilation (PCV) hose clamp at the resonator tee.
  28. Disconnect the PCV hose from the tee.

  29. Object Number: 1335460  Size: SH
  30. Remove the left PCV pipe bolt.
  31. Remove the left PCV pipe.

  32. Object Number: 1335608  Size: SH
  33. Remove the fuel injector pipes.

  34. Object Number: 1335588  Size: SH
  35. Remove the fuel return hose clips.
  36. Remove the fuel return hose from the injectors.

  37. Object Number: 1335536  Size: SH
  38. Disconnect the fuel injector electrical connectors.

  39. Object Number: 1335618  Size: SH
  40. Remove the fuel injector bracket bolts.

  41. Object Number: 1335621  Size: SH
  42. Install the J-46594 into the bolt hole in the fuel injector bracket.
  43. Install a flare nut wrench onto the J-46594 and pull back away from the fuel injector, until the injector releases from its seat.
  44. Remove the J-46594 .
  45. Remove the fuel injectors with brackets.

  46. Object Number: 1335628  Size: SH
  47. If necessary, remove the fuel injector bracket pins.
  48. Remove and discard the copper washer from the fuel injector bore.
  49. Remove and discard the O-ring from the fuel injector.

Fuel Injector Cleaning and Inspection

Important: If reusing the old injectors perform the following:


    Object Number: 1336202  Size: SH
  1. Use a soft bristle non-metallic brush and Top Engine Cleaner, GM P/N 1052626 or equivalent, to remove any deposits from the nozzle tip (1) and the copper washer sealing area (2) before re-installation.
  2. Inspect the fuel injector nozzle tip (1) for any signs of discoloration (dark yellow, tan or blue) due to excessive heat.
  3. Replace the injector if any damage is found.

  4. Object Number: 1336212  Size: SH
  5. Clean the fuel injector high pressure line.
  6. Inspect the fuel injector line for excessive corrosion or damage to the sealing surfaces (1, 2). Replace the line if any damage is found.

Injector Bore Cleaning

Important: The procedure below will aid in the cleaning of carbon deposits from the injector sleeve during an injector replacement

  1. Install the EN-47909-2 Radial Brush (brass), to the EN-47909-1 Handle Assembly.
  2. Insert the brush into the injector bore and rotate the handle in order to break loose any carbon deposits from the injector bore walls and the combustion deck hole.
  3. Caution: Wear safety glasses in order to avoid eye damage.

  4. Using compressed air, evacuate any debris from the injector bore.
  5. Remove the radial brush from the handle assembly.
  6. Install the EN-47909-3 Axial Brush (nylon), to the EN-47909-1.
  7. Insert the axial brush into the injector bore and rotate the handle while also applying a slight downward pressure, in order to force the brush ends into the bottom corners of the injector bore.
  8. Caution: Wear safety glasses in order to avoid eye damage.

  9. Using compressed air, evacuate any debris from the injector bore.
  10. Notice: Do not allow excessive amounts of solvent to go into the cylinder during cleaning. Failure to do so may cause engine damage upon startup.

  11. Lightly dampen EN-47909-20 Cotton Swab with Top Engine Cleaner, GM P/N 1052626 (Canadian P/N 993026) or equivalent, and wipe away any deposits from the injector bore.
  12. Inspect the injector bore for any deposits and repeat brushing if necessary.
  13. Caution: Keep hands and face clear of glow plug holes while cranking. Hot liquid or gases may be expelled during cranking.

    Caution: Wear safety glasses in order to avoid eye damage.

  14. If necessary, crank the engine in order to expel any solvent before starting the engine.
  15. 10.1. Remove the glow plugs. Refer to Glow Plug Replacement - Bank 1 and/or Glow Plug Replacement - Bank 2 .
    10.2. Disable the fuel system.
    10.3. Remove the ignition (Ign) B relay.
    10.4. Crank the engine in order to expel any excessive solvent.
    10.5. Using the cotton swabs supplied with the kit, wipe the injector bore clean of any solvent and/or debris.
    10.6. Reinstall the ignition (Ign) B relay.
    10.7. Enable the fuel system.
    10.8. Reinstall the glow plugs. Refer to Glow Plug Replacement - Bank 1 and/or Glow Plug Replacement - Bank 2 .

Installation Procedure


    Object Number: 1335628  Size: SH
  1. Install a NEW O-ring onto the fuel injector.
  2. Install a NEW copper washer to the fuel injector bore.
  3. If necessary, install the fuel injector bracket pins.

  4. Object Number: 1335621  Size: SH
  5. Install the fuel injectors with brackets.
  6. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1335618  Size: SH
  7. Install the fuel injector bracket bolts.
  8. Tighten
    Tighten the bolts to 30 N·m (22 lb ft).


    Object Number: 1335536  Size: SH
  9. Connect the fuel injector electrical connectors.

  10. Object Number: 1335588  Size: SH
  11. Install the fuel return hose to the injectors.
  12. Install the fuel return hose clips.

  13. Object Number: 1335608  Size: SH
  14. Install the fuel injector pipes.
  15. Tighten
    Tighten the fittings to 41 N·m (30 lb ft).


    Object Number: 1335460  Size: SH
  16. Install the left PCV pipe.
  17. Install the left PCV pipe bolt.
  18. Tighten
    Tighten the bolt to 18 N·m (13 lb ft).


    Object Number: 1335454  Size: SH
  19. Connect the PCV hose to the tee.
  20. Position the left PCV hose clamp at the resonator tee.

  21. Object Number: 1335531  Size: SH
  22. Connect the glow plug controller electrical connectors.

  23. Object Number: 1334948  Size: SH
  24. Install the main electrical harness bracket.
  25. Install the main electrical harness bracket bolts.
  26. Tighten
    Tighten the bolts to 21 N·m (15 lb ft).

  27. Connect the barometric sensor electrical connector.
  28. Install the engine wire harness to the clip.

  29. Object Number: 1334916  Size: SH
  30. Install the main electrical connectors to the bracket.
  31. Install the engine harness main electrical connector screws.
  32. Tighten
    Tighten the screws to 10 N·m (89 lb in).


    Object Number: 674653  Size: SH
  33. Connect the engine harness main connectors.
  34. Remove the tape from the turbocharger openings.
  35. Install the charged air cooler inlet pipe. Refer to Charged Air Cooler Hoses/Pipes Replacement in Engine Mechanical - 6.6L (LLY).
  36. If the number 8 injector required removal, perform steps 25-31.
  37. Install the left side engine mount. Refer to Engine Mount Bracket Replacement - Left Side in Engine Mechanical - 6.6L (LLY).
  38. If equipped with an automatic transmission, install the transmission filler tube. Refer to Transmission Fluid Filler Tube and Seal Replacement .
  39. If equipped with an automatic transmission, install the left side transmission mount to the transmission. Refer to Transmission Mount Replacement in Automatic Transmission - Allison.
  40. If equipped with a manual transmission, install the left side transmission mount bracket to the transmission. Refer to Transmission Mount Bracket Replacement in Manual Transmission ZF S6-650.
  41. Install the oil fill tube. Refer to Oil Filler Tube Replacement .
  42. Install the fan to the engine. Refer to Fan Replacement .
  43. Install the air cleaner . Refer to Air Cleaner Replacement .
  44. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  45. Install the engine cover, if required. Refer to Engine Cover Replacement in Interior Trim.
  46. Prime the fuel system. Refer to Fuel System Priming .
  47. Start the engine. If the engine stalls, repeat the above step.
  48. Once the engine starts, inspect for fuel leaks.

Fuel Injector Replacement Right

Tools Required

    • EN-47909 Injector Bore and Sleeve Cleaning Kit
    • J 44639 Fuel Injector Removal Tool

Removal Procedure


    Object Number: 1335614  Size: SH
  1. Remove the engine cover. Refer to Engine Cover Replacement in Interior Trim.
  2. Remove the air cleaner . Refer to Air Cleaner Replacement .
  3. Remove the charged air cooler outlet from the intake. Refer to Charged Air Cooler Hoses/Pipes Replacement in Engine Mechanical - 6.6L (LLY).
  4. Remove the fuel injection control module (FICM). Refer to Fuel Injector Control Module Replacement .
  5. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  6. Remove the fuel injector pipes.

  7. Object Number: 1335592  Size: SH
  8. Remove the fuel return hose clips.
  9. Remove the fuel return hose from the injectors.

  10. Object Number: 1335536  Size: SH
  11. Disconnect the fuel injector electrical connectors.

  12. Object Number: 1335619  Size: SH
  13. Remove the fuel injector bracket bolts.

  14. Object Number: 1335625  Size: SH
  15. Install the J-46594 into the bolt hole in the fuel injector bracket.
  16. Install a flare nut wrench onto the J-46594 and pull back away from the fuel injector, until the injector releases from its seat.
  17. Remove the J-46594 .
  18. Remove the fuel injectors with brackets.

  19. Object Number: 1335628  Size: SH
  20. If necessary, remove the fuel injector bracket pins.
  21. Remove and discard the copper washer from the fuel injector bore.
  22. Remove and discard the O-ring from the fuel injector.

Fuel Injector Cleaning and Inspection

Important: If reusing the old injectors perform the following:


    Object Number: 1336202  Size: SH
  1. Use a soft bristle non-metallic brush and Top Engine Cleaner, GM P/N 1052626 or equivalent, to remove any deposits from the nozzle tip (1) and the copper washer sealing area (2) before re-installation.
  2. Inspect the fuel injector nozzle tip (1) for any signs of discoloration (dark yellow, tan or blue) due to excessive heat.
  3. Replace the injector if any damage is found.

  4. Object Number: 1336212  Size: SH
  5. Clean the fuel injector high pressure line.
  6. Inspect the fuel injector line for excessive corrosion or damage to the sealing surfaces (1, 2). Replace the line if any damage is found.

Injector Bore Cleaning

Important: The procedure below will aid in the cleaning of carbon deposits from the injector sleeve during an injector replacement

  1. Install the EN-47909-2 Radial Brush (brass), to the EN-47909-1 Handle Assembly.
  2. Insert the brush into the injector bore and rotate the handle in order to break loose any carbon deposits from the injector bore walls and the combustion deck hole.
  3. Caution: Wear safety glasses in order to avoid eye damage.

  4. Using compressed air, evacuate any debris from the injector bore.
  5. Remove the radial brush from the handle assembly.
  6. Install the EN-47909-3 Axial Brush (nylon), to the EN-47909-1.
  7. Insert the axial brush into the injector bore and rotate the handle while also applying a slight downward pressure, in order to force the brush ends into the bottom corners of the injector bore.
  8. Caution: Wear safety glasses in order to avoid eye damage.

  9. Using compressed air, evacuate any debris from the injector bore.
  10. Notice: Do not allow excessive amounts of solvent to go into the cylinder during cleaning. Failure to do so may cause engine damage upon startup.

  11. Lightly dampen EN-47909-20 Cotton Swab with Top Engine Cleaner, GM P/N 1052626 (Canadian P/N 993026) or equivalent, and wipe away any deposits from the injector bore.
  12. Inspect the injector bore for any deposits and repeat brushing if necessary.
  13. Caution: Keep hands and face clear of glow plug holes while cranking. Hot liquid or gases may be expelled during cranking.

    Caution: Wear safety glasses in order to avoid eye damage.

  14. If necessary, crank the engine in order to expel any solvent before starting the engine.
  15. 10.1. Remove the glow plugs. Refer to Glow Plug Replacement - Bank 1 and/or Glow Plug Replacement - Bank 2 .
    10.2. Disable the fuel system.
    10.3. Remove the ignition (Ign) B relay.
    10.4. Crank the engine in order to expel any excessive solvent.
    10.5. Using the cotton swabs supplied with the kit, wipe the injector bore clean of any solvent and/or debris.
    10.6. Reinstall the ignition (Ign) B relay.
    10.7. Enable the fuel system.
    10.8. Reinstall the glow plugs. Refer to Glow Plug Replacement - Bank 1 and/or Glow Plug Replacement - Bank 2 .

Installation Procedure


    Object Number: 1335628  Size: SH
  1. Install a NEW O-ring onto the fuel injector.
  2. Install a NEW copper washer to the fuel injector bore.
  3. Install the fuel injector bracket pins.

  4. Object Number: 1335625  Size: SH
  5. Install the fuel injectors with brackets.
  6. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1335619  Size: SH
  7. Install the fuel injector bracket bolts.
  8. Tighten
    Tighten the bolts to 30 N·m (22 lb ft).


    Object Number: 1335536  Size: SH
  9. Connect the fuel injector electrical connectors.

  10. Object Number: 1335592  Size: SH
  11. Install the fuel return hose to the injectors.
  12. Install the fuel return hose clips.

  13. Object Number: 1335614  Size: SH
  14. Install the fuel injector pipes.
  15. Tighten
    Tighten the fittings to 41 N·m (30 lb ft).

  16. Install the FICM. Refer to Fuel Injector Control Module Replacement .
  17. Important: Lubricate the end of the duct prior to installation.

  18. Install the charged air cooler outlet to the intake. Refer to Charged Air Cooler Hoses/Pipes Replacement in Engine Mechanical - 6.6L (LLY).
  19. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  20. Install the air cleaner . Refer to Air Cleaner Replacement .
  21. Install the engine cover. Refer to Engine Cover Replacement in Interior Trim.
  22. Prime the fuel system. Refer to Fuel System Priming .
  23. Start the engine. If the engine stalls, repeat the above step.
  24. Once the engine starts, inspect for fuel leaks.