GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2007 🢒 Express - AWD 🢒 Engine 🢒 Engine Controls and Fuel - 6.6L (LBZ and LLY) 🢒 Engine Wiring Harness Assembly Replacement

Removal Procedure

    Object Number: 1732768 Size: SH
  1. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection .
  2. Remove the exhaust gas recirculation (EGR) cooler tube. Refer to Exhaust Gas Recirculation Valve Cooler Replacement .
  3. Remove the thermostat housing crossover. Refer to Thermostat Housing Crossover Replacement .
  4. Remove the turbocharger vane position sensor. Refer to Turbocharger Vane Position Sensor Replacement .
  5. Remove the left engine wiring harness bracket bolts (1).
  6. Remove the left glow plug nuts (2).

    7. Object Number: 1732359 Size: SH

    Notice: Label all the injector electrical connectors before the connectors are removed in order to prevent reconnecting to the wrong injector. Failure to properly connect the injectors in the correct sequence will cause severe engine damage.

  7. Remove the engine wiring harness electrical connectors from the left fuel injectors.

    8. Object Number: 1662873 Size: SH
  8. Disconnect the engine wiring harness electrical connector from the glow plug control module.
  9. Disconnect the engine wiring harness electrical connector from the intake air temperature (IAT) sensor.
  10. Disconnect the left side engine wiring harness main electrical connector.
  11. Remove the left side engine wiring harness main connector bolt from the bracket.

    12. Object Number: 1732300 Size: SH
  12. Disconnect the engine wiring harness electrical connector from the fuel temperature sensor.

    13. Object Number: 1335546 Size: SH
  13. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
  14. Disconnect the engine wiring harness electrical connector (2) from the oil pressure sensor.
  15. Disconnect the engine wiring harness electrical connector from the oil level sensor.

    16. Object Number: 1335549 Size: SH
  16. Remove the engine wiring harness left side ground bolt.
  17. Remove the engine wiring harness from the clip secured behind one of the front cover bolts.

    18. Object Number: 1662872 Size: SH
  18. Remove the engine wiring right side ground bolt.
  19. Lower the vehicle.

    20. Object Number: 1334862 Size: SH
  20. Disconnect the engine wiring harness electrical connector from the camshaft position (CMP) sensor.
  21. Remove the engine wiring harness from behind the clip attached to the engine block.

    22. Object Number: 1335470 Size: SH
  22. Disconnect the engine wiring harness electrical connector from the crankshaft position (CKP) sensor.

    23. Object Number: 1732769 Size: SH
  23. Remove the right engine wiring harness bracket bolts (1) and nut (2).
  24. Remove the glow plug nuts (3).

    25. Object Number: 1734476 Size: SH
  25. Disconnect the engine wiring harness electrical connector from the fuel pressure regulator.
  26. Disconnect the right side main engine wiring harness electrical connector.
  27. Remove the right side main engine wiring harness connector bolt.

    28. Object Number: 1335536 Size: SH

    Notice: Label all the injector electrical connectors before the connectors are removed in order to prevent reconnecting to the wrong injector. Failure to properly connect the injectors in the correct sequence will cause severe engine damage.

  28. Disconnect the engine wiring harness electrical connectors from the right side fuel injectors.

    29. Object Number: 1335540 Size: SH
  29. Disconnect the engine wiring harness electrical connector from the turbocharger vane control solenoid valve.

    30. Object Number: 1732190 Size: SH
  30. Disconnect the engine wiring harness electrical connector (1) from the fuel rail pressure sensor.
  31. Remove the fuel rail pressure sensor wiring harness clip from the bracket.

    32. Object Number: 1731918 Size: SH
  32. Remove the engine wiring harness.

Installation Procedure

    Object Number: 1731918 Size: SH
  1. Install the engine wiring harness.

    2. Object Number: 1732190 Size: SH
  2. Connect the engine wiring harness electrical connector (1) to the fuel rail pressure sensor.
  3. Install the fuel rail pressure sensor wiring harness clip to the bracket.

    4. Object Number: 1335540 Size: SH
  4. Connect the engine wiring harness electrical connector to the turbocharger vane control solenoid valve.

    5. Object Number: 1335536 Size: SH

    Notice: Label all the injector electrical connectors before the connectors are removed in order to prevent reconnecting to the wrong injector. Failure to properly connect the injectors in the correct sequence will cause severe engine damage.

  5. Connect the engine wiring harness electrical connectors to the right side fuel injectors.

    6. Object Number: 1734476 Size: SH
  6. Connect the engine wiring harness electrical connector to the fuel pressure regulator.

    7. Notice: Refer to Fastener Notice in the Preface section.

  7. Position the right side main engine wiring harness connector to the bracket and install the connector bolt.

    8. Tighten
    Tighten the bolt to 10 N·m (89 lb in).

  8. Connect the right side main engine wiring harness electrical connector.

    9. Object Number: 1732769 Size: SH
  9. Install the engine wiring harness to the glow plugs and install the glow plug nuts (3).

    10. Tighten
    Tighten the nuts to 1.7 N·m (15 lb in).

  10. Position the right engine wiring harness bracket and install the bracket bolts (1) and nut (2).

    11. Tighten
    Tighten the bolts and nut to 10 N·m (89 lb in).


    Object Number: 1335470 Size: SH
  11. Connect the engine wiring harness electrical connector to the CKP sensor.

    12. Object Number: 1334862 Size: SH
  12. Connect the engine wiring harness electrical connector to the CMP sensor.
  13. Install the engine wiring harness behind the clip attached to the engine block.

    14. Object Number: 1662872 Size: SH
  14. Raise and support the vehicle.
  15. Position the engine wiring right side ground and install the bolt.

    16. Tighten
    Tighten the bolt to 41 N·m (30 lb ft).


    Object Number: 1335549 Size: SH
  16. Position the engine wiring harness left side ground and install the bolt.

    17. Tighten
    Tighten the bolt to 40 N·m (29 lb ft).

  17. Install the engine wiring harness behind the clip secured to the front cover.

    18. Object Number: 1335546 Size: SH
  18. Lower the vehicle.
  19. Connect the engine wiring harness electrical connector (2) to the oil pressure sensor.
  20. Connect the engine wiring harness electrical connector to the oil level sensor.

    21. Object Number: 1732300 Size: SH
  21. Connect the engine wiring harness electrical connector to the fuel temperature sensor.

    22. Object Number: 1662873 Size: SH
  22. Connect the engine wiring harness electrical connector to the glow plug control module.
  23. Connect the engine wiring harness electrical connector to the IAT sensor.
  24. Position the left side engine wiring harness main electrical connector to the bracket and install the connector bolt.

    25. Tighten
    Tighten the bolt to 10 N·m (89 lb in).


    Object Number: 1732359 Size: SH

    Notice: Label all the injector electrical connectors before the connectors are removed in order to prevent reconnecting to the wrong injector. Failure to properly connect the injectors in the correct sequence will cause severe engine damage.

  25. Install the engine wiring harness electrical connectors to the left fuel injectors.

    26. Object Number: 1732768 Size: SH
  26. Install the engine wiring harness to the left glow plugs and install the glow plug nuts (2).

    27. Tighten
    Tighten the nuts to 1.7 N·m (15 lb in).

  27. Position the left engine wiring harness bracket and install the bracket bolts (1).

    28. Tighten
    Tighten the bolts to 10 N·m (89 lb ft).

  28. Install the turbocharger vane position sensor. Refer to Turbocharger Vane Position Sensor Replacement .
  29. Install the thermostat housing crossover. Refer to Thermostat Housing Crossover Replacement .
  30. Install the EGR cooler tube. Refer to Exhaust Gas Recirculation Valve Cooler Replacement .
  31. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection .