GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

    Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

  1. Disconnect the negative battery cable.
  2. Remove the crankshaft pulley from the engine. Refer to Crankshaft Pulley Replacement .
  3. Remove the timing belt from the engine. Refer to Timing Belt Replacement .
  4. Remove the valve rocker arm cover from the engine. Refer to Valve Rocker Arm Cover Replacement .

  5. Object Number: 510241  Size: SH
  6. Use an appropriate tool to hold the camshaft timing belt pulley.
  7. Remove the camshaft timing belt pulley bolt and camshaft timing belt pulley.

  8. Object Number: 166345  Size: SH
  9. Remove the timing belt inner cover (2).

  10. Object Number: 590974  Size: SH
  11. Remove the camshaft sensor (2), and the ground wire from the camshaft sensor housing (1).
  12. Remove the wiring harness clamp from the camshaft sensor housing.
  13. Important: In order to catch any oil, place a shop rag under the camshaft housing before removing it from the cylinder head.

  14. Remove the three camshaft sensor housing bolts and the camshaft sensor housing (1) from the cylinder head.

  15. Object Number: 262387  Size: SH
  16. Loosen all valve adjusting screw lock nuts (2), turn adjusting screws back all the way to allow all rocker arms to move freely.

  17. Object Number: 262392  Size: SH
  18. Gradually remove the 12 camshaft housing bolts in the sequence shown.
  19. Remove the camshaft from the cylinder head.
  20. Remove the camshaft oil seal from the camshaft.

Installation Procedure

  1. Apply clean engine oil to the following components:
  2. • Cams
    • Journals
    • The oil seal
  3. Install the camshaft to the cylinder head.

  4. Object Number: 262257  Size: SH

    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.

  5. After applying the engine oil to the housing bolts, tighten in the sequence shown.
  6. Tighten
    Tighten the camshaft housing bolts to 10 N·m (89 lb in).


    Object Number: 262265  Size: SH
  7. After applying engine oil to the oil seal lip (1), install the camshaft oil seal (1) to the housing until the oil seal is flush with the surface of the housing.
  8. Install the timing belt inner cover.

  9. Object Number: 262279  Size: SH

    Important: When installing the camshaft timing sprocket to the camshaft, verify that the pin on the camshaft fits the slot marked "E" on the sprocket.

  10. Install the camshaft timing sprocket (1).

  11. Object Number: 510248  Size: SH

    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.

  12. Use the camshaft timing sprocket bolt in order to secure the camshaft timing sprocket to the camshaft.
  13. Tighten
    Tighten the camshaft timing sprocket bolt to 60 N·m (44 lb ft).


    Object Number: 590974  Size: SH
  14. Install the camshaft sensor housing (1) to the cylinder head.
  15. Tighten
    Tighten the camshaft sensor housing bolts to 10 N·m (89 lb in).

  16. Install the camshaft sensor and ground wire to the cam sensor housing.
  17. Tighten
    Tighten the camshaft sensor bolt to 10 N·m (89 lb in).

  18. Temporarily install the valve rocker arm cover.
  19. Install the timing belt. Refer to Timing Belt Replacement .
  20. Remove the valve rocker arm cover.
  21. Adjust the valve lash. Refer to Valve Lash Adjustment .
  22. Install the valve rocker arm cover. Refer to Valve Rocker Arm Cover Replacement .
  23. Install the crankshaft pulley. Refer to Timing Belt Replacement .
  24. Connect the negative battery cable.
  25. Tighten
    Tighten the battery cable to 15 N·m (11 lb ft).