GM Service Manual Online
For 1990-2009 cars only

Removal Procedure


    Object Number: 679598  Size: SH
  1. Remove the engine sight shield, if required. Refer to Upper Intake Manifold Sight Shield Replacement .
  2. Remove the connector position assurance (CPA) lock.
  3. Disconnect the main electrical connector (1) to the ignition coil wire harness.
  4. Remove the harness clips (2).
  5. Reposition the engine harness, if necessary.
  6. Remove the spark plug wires from the ignition coils.
  7. • Twist each plug wire 1/2 turn.
    • Pull only on the boot in order to remove the wire from the ignition coil.

    Object Number: 664355  Size: SH
  8. Remove the secondary air injection (AIR) pipe bolt.

  9. Object Number: 664356  Size: SH
  10. Reposition the AIR pipe hose clamp at the pipe.
  11. Remove the AIR pipe hose from the AIR pipe.
  12. Reposition the AIR pipe clamps at the check valves.
  13. Remove the AIR pipe (1).

  14. Object Number: 688018  Size: SH
  15. Reposition the surge tank/heater hoses from the heater hose bracket.
  16. Remove the heater hose bracket nut and bracket.

  17. Object Number: 647792  Size: SH
  18. Remove the ignition coil bracket studs from the rocker arm cover.
  19. Remove the ignition coils and bracket from the rocker cover.

  20. Object Number: 647795  Size: SH
  21. Remove the vent hose from the throttle body and valve rocker arm cover.

  22. Object Number: 260084  Size: SH
  23. Remove the valve rocker arm cover bolts.
  24. Remove the valve rocker arm cover.

  25. Object Number: 490696  Size: SH
  26. Remove the gasket (1) from the rocker cover.
  27. Discard the OLD gasket.

  28. Object Number: 647798  Size: SH
  29. Remove the oil fill cap from the oil fill tube.
  30. Remove the oil fill tube from the rocker cover, if required.
  31. Discard the oil fill tube.
  32. Clean and inspect the rocker arm cover. Refer to Valve Rocker Arm Cover Cleaning and Inspection in the Engine Unit Repair Manual.

Installation Procedure

Important: 

   • All gasket surfaces should be free of oil or other foreign material during assembly.
   • DO NOT reuse the valve rocker arm cover gasket.
   • The valve rocker arm cover bolt grommets may be reused.
   • If the oil fill tube has been removed from the rocker arm cover, install a NEW fill tube during assembly.


    Object Number: 647798  Size: SH
  1. Lubricate the O-ring seal of the NEW oil fill tube with clean engine oil.
  2. Insert the NEW oil fill tube into the rocker arm cover.
  3. Rotate the tube clockwise until locked in the proper position.

  4. Install the oil fill cap into the tube.
  5. Rotate the cap clockwise until locked in the proper position.


    Object Number: 490696  Size: SH
  6. Install a NEW rocker cover gasket (1) into the valve rocker arm cover.

  7. Object Number: 260084  Size: SH
  8. Install the valve rocker arm cover onto the cylinder head.
  9. Install new rocker arm cover grommets, if necessary.
  10. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  11. Install the rocker arm cover bolts and grommets.
  12. Tighten
    Tighten the valve rocker arm cover bolts to 12 N·m (106 lb in).


    Object Number: 647795  Size: SH
  13. Install the vent hose to the throttle body and valve rocker arm cover.

  14. Object Number: 647792  Size: SH
  15. Apply threadlock GM P/N 12345382 or equivalent to the threads of the bracket bolts.
  16. Install the ignition coils and bracket to the rocker arm cover.
  17. Install the ignition coil bracket studs to the rocker cover.
  18. Tighten
    Tighten the ignition coil bracket studs to 12 N·m (106 lb in).


    Object Number: 688018  Size: SH
  19. Install the heater hose bracket and nut.
  20. Tighten
    Tighten the heater hose bracket nut to 9 N·m (80 lb in).

  21. Position the surge tank/heater hoses to the heater hose bracket.

  22. Object Number: 664356  Size: SH
  23. Install pipe (1).
  24. Position the AIR pipe clamps at the check valves.
  25. Install the AIR pipe hose to the AIR pipe.
  26. Position the AIR pipe hose clamp at the pipe.

  27. Object Number: 664355  Size: SH
  28. Install the AIR pipe bolt.
  29. Tighten
    Tighten the AIR pipe bolt to 25 N·m (18 lb ft).


    Object Number: 679598  Size: SH
  30. Install the spark plug wires to the ignition coils.
  31. Position the engine harness, if necessary.
  32. Install the harness clips (2).
  33. Connect the main electrical connector (1) feeding the ignition coils.
  34. Install the CPA lock.
  35. Install the engine sight shield, if required. Refer to Upper Intake Manifold Sight Shield Replacement .