GM Service Manual Online
For 1990-2009 cars only

    Object Number: 1207128  Size: SH

    Important: Store all components in a clean location.

  1. Remove the camshaft position (CMP) sensor bolt.
  2. Remove the CMP sensor.
  3. Remove and discard the CMP sensor O-ring.

  4. Object Number: 612489  Size: SH
  5. Remove the chain guide access plugs located in the cylinder heads. Ensure the O-ring seal is on each access plug.

  6. Object Number: 212695  Size: SH
  7. Remove the right secondary drive chain tensioner bolts.
  8. Remove the right secondary camshaft drive chain tensioner allowing it to expand as you remove it.

  9. Object Number: 685331  Size: SH
  10. Remove the upper right secondary camshaft drive chain guide bolt.
  11. Notice: Refer to Torque Reaction Against Timing Drive Chain Notice in the Preface section.


    Object Number: 1207124  Size: SH
  12. Remove the camshaft sprocket bolts from the camshafts. Use an open wrench on the hex cast near the front of each camshaft to prevent engine rotation when loosening the camshaft sprocket bolts.
  13. Lift the secondary camshaft drive chain from the camshaft sprocket teeth and slide the camshaft sprockets off of the camshafts.

  14. Object Number: 685335  Size: SH
  15. Remove the right secondary camshaft drive chain.

  16. Object Number: 685338  Size: SH
  17. Remove the right secondary camshaft drive chain shoe bolt.

  18. Object Number: 685343  Size: SH
  19. Remove the right secondary camshaft drive chain shoe.

  20. Object Number: 685347  Size: SH
  21. Remove the lower right secondary camshaft drive chain guide bolt.

  22. Object Number: 685348  Size: SH
  23. Remove the right secondary camshaft drive chain guide.