GM Service Manual Online
For 1990-2009 cars only

Notice: The OBD II ignition system distributor driven gear and rotor can be installed in multiple positions. Be sure to mark the following positions:

   • The distributor driven gear
   • The distributor shaft
   • The rotor holes for the same mounting position upon reassembly
Installing the driven gear 180° off, or locating the rotor in the wrong holes, will cause a no start condition. Also premature wear and damage may result.

Notice: Failure to keep cleaning agents away from the distributor Hall Effect switch may cause premature failure.


    Object Number: 4371  Size: SH
  1. Remove the two screws that hold the distributor cap to the housing.

  2. Object Number: 4372  Size: SH
  3. Remove the cap from the housing.

  4. Object Number: 4354  Size: SH
  5. Remove the two screws from the rotor.

  6. Object Number: 4357  Size: SH
  7. Remove the rotor.

  8. Object Number: 4347  Size: SH
  9. Note the locating holes the rotor was removed from.

  10. Object Number: 4341  Size: SH
  11. Remove the two screws that hold the Hall Effect switch.

  12. Object Number: 6336  Size: SH
  13. Line up the square cut hole in the vane wheel with the switch.

  14. Object Number: 4340  Size: SH
  15. Remove the Hall Effect switch.

  16. Object Number: 4358  Size: SH
  17. Remove the roll pin from the distributor shaft.
  18. • Note the dimple located below the roll pin hole on one side of the gear.
    • The dimple will be used to properly orient the gear on the shaft during reassembly.
  19. Drive out the roll pin with a suitable punch, wear safety glasses.

  20. Object Number: 4346  Size: SH
  21. Remove the driven gear from the distributor shaft.

  22. Object Number: 4344  Size: SH
  23. Remove the round washer.

  24. Object Number: 4343  Size: SH
  25. Remove the tang washer.

  26. Object Number: 4342  Size: SH
  27. Remove the distributor shaft from the housing.
  28. • If the shaft cannot be removed from the distributor housing due to varnish buildup, use a cloth dampened with varnish remover to clean the shaft.
    • Do not allow the varnish remover to travel up the distributor shaft. This may remove the lubrication from the shaft bushings.