GM Service Manual Online
For 1990-2009 cars only

    Notice: Retrieve the damaged glow plug from the cylinder or serious engine damage will occur.

  1. Remove the injector nozzle from the failed glow plug cylinder.
  2. Place a shop towel in the precup chamber in order to capture the glow plug tip when it breaks off from the glow plug shell upon removal (this will keep the tip from dropping into the cylinder).
  3. Use a pair of needle nose pliers (or other gripping device) in order to grasp the tip and remove it from the precup chamber.
  4. Remove the shop towel and reinstall the injector nozzle.
  5. If the glow plug tip has already broken off the glow plug and it is not retrievable from the precup chamber, remove the cylinder head so that the tip can be retrieved from the piston cylinder. Refer to Cylinder Head Replacement .