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For 1990-2009 cars only

Camshaft Replacement - Left Side First Design

Special Tools

    • EN 46108 Timing Chain Retention Tool
    • EN 46111 Crankshaft Rotation Socket

Important: To identify a camshaft drive design, refer to Camshaft Timing Drive Design Identification .

Removal Procedure

  1. Remove the lower intake manifold. Refer to Lower Intake Manifold Replacement .
  2. Remove the left bank camshaft cover. Refer to Camshaft Cover Replacement - Left Side .
  3. Remove the camshaft sensors. Refer to Camshaft Position Sensor Replacement - Bank 2 (Left Side) Exhaust and Camshaft Position Sensor Replacement - Bank 2 (Left Side) Intake .
  4. Remove the camshaft position actuator solenoid. Refer to Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 2 (Left Side) Intake .
  5. Remove the crankshaft balancer. Refer to Crankshaft Balancer Replacement .

  6. Object Number: 1306293  Size: SH
  7. Rotate the crankshaft with the EN 46111 until the camshafts are in a neutral (low tension) position. The camshaft flats will be parallel with the camshaft cover rail (1).
  8. 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.

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


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


    Object Number: 1306391  Size: SH

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

  13. Mark the timing chain and the respective locations on the camshaft position actuators (1-4).
  14. Remove the camshaft position actuator bolt.
  15. Remove the camshafts. Refer to Camshaft Removal - Left Side .

Installation Procedure


    Object Number: 1306391  Size: SH

    Important: 

       • Ensure that the marks on the camshaft position actuator and the timing chain (1-4) are aligned.
       • DO NOT tighten the camshaft position actuator bolt at this time.

  1. Locate the camshafts to the cylinder head and assemble the camshaft actuators to the camshafts.
  2. Install the camshafts and the camshaft bearing caps. Refer to Camshaft Installation - Left Side .
  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. Install and tighten the camshaft position actuators. Refer to Camshaft Position Actuator Installation - Left Side Intake and Camshaft Position Actuator Installation - Left Side Exhaust .
  6. Install the intake camshaft position actuator solenoid. Refer to Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 2 (Left Side) Intake .
  7. Install the camshaft sensors. Refer to Camshaft Position Sensor Replacement - Bank 2 (Left Side) Exhaust and Camshaft Position Sensor Replacement - Bank 2 (Left Side) Intake .
  8. Install the crankshaft balancer. Refer to Crankshaft Balancer Replacement .
  9. Install the camshaft cover. Refer to Camshaft Cover Replacement - Left Side .
  10. Install the lower intake manifold. Refer to Lower Intake Manifold Replacement .

Camshaft Replacement - Left Side Second Design

Special Tools

    • EN-48313 Timing Chain Retention Tool
    • EN 46111 Crankshaft Rotation Socket

Important: To identify a camshaft drive design, refer to Camshaft Timing Drive Design Identification .

Removal Procedure

  1. Remove the lower intake manifold. Refer to Lower Intake Manifold Replacement .
  2. Remove the left bank camshaft cover. Refer to Camshaft Cover Replacement - Left Side .
  3. Remove the camshaft sensors. Refer to Camshaft Position Sensor Replacement - Bank 2 (Left Side) Exhaust and Camshaft Position Sensor Replacement - Bank 2 (Left Side) Intake .
  4. Remove the camshaft position actuator solenoid. Refer to Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 2 (Left Side) Intake .
  5. Remove the crankshaft balancer. Refer to Crankshaft Balancer Replacement .

  6. Object Number: 1306293  Size: SH
  7. Rotate the crankshaft with the EN 46111 until the camshafts are in a neutral (low tension) position. The camshaft flats will be parallel with the camshaft cover rail (1).
  8. 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.

  9. Loosen the camshaft position actuator bolt.

  10. Object Number: 1858601  Size: SH
  11. Unscrew the EN-48313 so that the legs of the tool are retracted.
  12. Insert the EN-48313 between the camshaft actuators, rearward of the timing chain until the bottom line that is scribed in the body of the tool (2) is adjacent to the top surface of the cylinder head (1). This is the approximate installed position.

  13. Object Number: 1858602  Size: SH

    Important: The engine front cover is removed for clarity in the following graphics, but NOT required to perform the procedure.

  14. Ensure that the feet (4) on the legs of the tool are facing the front of the engine.
  15. Partially expand the legs (1, 3) of the EN-48313 by turning the T-shaped handle clockwise.
  16. Insert the leg of the tool (1) behind the timing chain guide (2).
  17. Continue expanding the EN-48313 until the legs (1, 3) contact the timing chain. Do not tighten at this time.

  18. Object Number: 1858603  Size: SH

    Important: Ensure that the foot (1) of the EN-48313 is engaged into one of the link pockets to prevent tool slippage during tightening of the EN-48313 .

  19. Hand tighten the EN-48313 .
  20. Notice: Refer to Torque Reaction Against Timing Drive Chain Notice in the Preface section.

  21. Use an open end wrench on the hex cast into the left intake and exhaust camshafts and rotate the camshafts toward each other in order to create slack in the chain between the actuators.

  22. Object Number: 1858605  Size: SH
  23. The EN-48313 is now properly installed to hold the timing chain in position.

  24. Object Number: 1306391  Size: SH

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

  25. Mark the timing chain and the respective locations on the camshaft position actuators (1-4).
  26. Remove the camshaft position actuator bolt.
  27. Remove the camshafts. Refer to Camshaft Removal - Left Side .

Installation Procedure


    Object Number: 1306391  Size: SH

    Important: 

       • Ensure that the marks on the camshaft position actuator and the timing chain (1-4) are aligned.
       • DO NOT tighten the camshaft position actuator bolt at this time.

  1. Locate the camshafts to the cylinder head and assemble the camshaft actuators to the camshafts.
  2. Install the camshafts and the camshaft bearing caps. Refer to Camshaft Installation - Left Side .
  3. Remove the EN-48313 .
  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. Install and tighten the camshaft position actuators. Refer to Camshaft Position Actuator Installation - Left Side Intake and Camshaft Position Actuator Installation - Left Side Exhaust .
  6. Install the intake camshaft position actuator solenoid. Refer to Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 2 (Left Side) Intake .
  7. Install the camshaft sensors. Refer to Camshaft Position Sensor Replacement - Bank 2 (Left Side) Exhaust and Camshaft Position Sensor Replacement - Bank 2 (Left Side) Intake .
  8. Install the crankshaft balancer. Refer to Crankshaft Balancer Replacement .
  9. Install the camshaft cover. Refer to Camshaft Cover Replacement - Left Side .
  10. Install the lower intake manifold. Refer to Lower Intake Manifold Replacement .