GM Service Manual Online
For 1990-2009 cars only

Special Tools

    • EN-48245 Timing Belt Adjuster - Camshaft Holder
    • EN-48246 Timing Belt Adjuster - Crankshaft Holder

Adjustment Procedure


    Object Number: 1820584  Size: SH
  1. Remove the vacuum pump. Refer to Vacuum Pump Assembly Replacement .

  2. Object Number: 1822550  Size: SH
  3. Rotate the camshaft and align the hole on the top point.
  4. Rotate the crankshaft and align the mark on the crankshaft sprocket.

  5. Object Number: 1822551  Size: SH
  6. Remove the crankshaft holder hole cap bolt (1).
  7. Insert EN-48246 into the crankshaft holder hole (2).
  8. Important:  Rotate the crankshaft sprocket a little and simultaneously insert the crankshaft holder.

  9. Install the EN-48245 onto the camshaft rear side (3).

  10. Object Number: 1820518  Size: SH
  11. Align the sprocket mark on the timing belt rear cover mark.

  12. Object Number: 1820436  Size: SH
  13. Install the camshaft sprocket with the retaining bolt finger tight.
  14. Install the timing belt.
  15. Install the timing belt tensioner with the retaining bolt finger tight.

  16. Object Number: 1822553  Size: SH
  17. Turn the hex-key (1) tab in a counterclockwise direction to tension the belt. Turn until the point aligns with the notch (2).
  18. Aligning with notch, install the timing belt tensioner bolt.
  19. Install the camshaft sprocket bolt.
  20. Tighten

        • Tighten the timing belt tensioner bolt to 25 N·m (18.4 lb in).
        • Tighten the camshaft sprocket bolt to 133 N·m (98.1 lb in).
  21. Remove the EN-48245 and EN-48246 .
  22. Turn the crankshaft in a clockwise direction 2 cycles and check the mark on the crankshaft sprocket.
  23. Important: If the timing marks are not aligned, repeat steps 4-10 and recheck the timing marks. Alignment of timing marks is critical for engine performance and emissions.

  24. After alignment of the timing belt, install the crankshaft holder hole cap bolt.
  25. Tighten
    Tighten the crankshaft holder hole cap bolt to 30 N·m (22.1 lb ft).