GM Service Manual Online
For 1990-2009 cars only

Tools Required

EN 46108 Timing Chain Retention Tool

Removal Procedure

  1. Remove the upper intake manifold with the lower intake manifold. Refer to Lower Intake Manifold Replacement .
  2. Remove the camshaft cover. Refer to Camshaft Cover Replacement - Right Side .
  3. Remove the camshaft sensors. Refer to Camshaft Position Sensor Replacement - Bank 1 (Right Side) Exhaust and Camshaft Position Sensor Replacement - Bank 1 (Right Side) Intake .
  4. Remove the intake camshaft position actuator solenoid. Refer to Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 1 (Right Side) Intake .

  5. Object Number: 1306310  Size: SH

    Important: Rotate the crankshaft balancer in a clockwise rotation ONLY.

  6. Rotate the crankshaft using the crankshaft balancer bolt until the camshafts are in a neutral (low tension) position. The camshaft flats will be parallel with the camshaft cover rail (1).
  7. Notice: Refer to Torque Reaction Against Timing Drive Chain Notice in the Preface section.


    Object Number: 1340931  Size: SH

    Important: 

       • Use an open-end wrench at the camshaft hex to prevent camshaft/engine rotation.
       • DO NOT remove the camshaft position actuator bolt at this time.

  8. Loosen the camshaft position actuator bolt.
  9. Important: Ensure that the tips of the EN 46108 are fully engaged into the timing chain (3 and 4).


    Object Number: 1341287  Size: SH
  10. Install the EN 46108 (1 and 2) in order to retain the timing chain.
  11. Firmly tighten the EN 46108 nuts.


    Object Number: 1306457  Size: SH

    Important: Ensure that the camshaft timing chain and the camshaft position actuators are marked for proper assembly.

  12. Mark the timing chain and the respective locations on camshaft position actuators (15-18).
  13. Remove the right exhaust camshaft position actuator bolt.
  14. Remove the right exhaust camshaft actuator.

Installation Procedure


    Object Number: 1306457  Size: SH

    Important: 

       • Ensure that the marks on the camshaft position actuators and the timing chain (15-18) are aligned.
       • DO NOT tighten the camshaft position actuator bolt at this time.

  1. Assemble the camshaft actuator to the camshaft.
  2. Loosely install the camshaft actuator bolt.
  3. Remove the EN 46108 .
  4. Notice: Refer to Torque Reaction Against Timing Drive Chain Notice in the Preface section.


    Object Number: 1340931  Size: SH

    Important: Use an open-end wrench at the camshaft hex to prevent camshaft/engine rotation.

  5. Tighten the camshaft position actuator. Refer to Camshaft Position Actuator Installation - Right Side Exhaust.
  6. Install the crankshaft balancer. Refer to Crankshaft Balancer Installation .
  7. Install the intake camshaft position actuator solenoid. Refer to Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 1 (Right Side) Intake .
  8. Install the camshaft sensors. Refer to Camshaft Position Sensor Replacement - Bank 1 (Right Side) Exhaust and Camshaft Position Sensor Replacement - Bank 1 (Right Side) Intake .
  9. Install the camshaft cover. Refer to Camshaft Cover Replacement - Right Side .
  10. Install the upper intake manifold with the lower intake manifold. Refer to Lower Intake Manifold Replacement .