GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Caution: Observe the following service precautions:

   • Allow the engine to cool before removing the spark plugs. Attempting to remove spark plugs from a hot engine can cause the spark plugs to seize. This can damage the cylinder head threads.
   • Clean the spark plug recess area before removing the spark plug. Failure to do so can result in engine damage due to dirt or foreign material entering the cylinder head, or in contamination of the cylinder head threads. Contaminated threads may prevent proper seating of the new spark plug.
   • Use only the spark plugs specified for use in the vehicle. Do not install spark plugs that are either hotter or colder than those specified for the vehicle. Installing spark plugs of another type can severely damage the engine.

  1. Remove the air cleaner outlet duct, if required. Refer to Air Cleaner Outlet Duct Replacement.

  2. Object Number: 1608802  Size: SH
  3. Remove the left side spark plug wires from the spark plugs, if required.

  4. Object Number: 1608803  Size: SH
  5. Remove the right side spark plug wires from the spark plugs, if required.

  6. Object Number: 1587748  Size: SH
  7. Remove the spark plugs as needed.

Installation Procedure

Caution: Check the gap of all new and reconditioned spark plugs before installation. The pre-set gaps may have changed during handling. Use a round feeler gage to ensure an accurate check. Installing the spark plugs with the wrong gap can cause poor engine performance and may even damage the engine.


    Object Number: 1587748  Size: SH
  1. Gap the NEW spark plugs, if replacing. Refer to Ignition System Specifications.
  2. Caution: Refer to Fastener Caution in the Preface section.

  3. Install the spark plugs as needed.
  4. Tighten
    Tighten the plugs to 15 N·m (11 lb ft).


    Object Number: 1608803  Size: SH
  5. Install the right side spark plug wires to the spark plugs, if required.

  6. Object Number: 1608802  Size: SH
  7. Install the left side spark plug wires to the spark plugs, if required.
  8. Install the air cleaner outlet duct, if required. Refer to Air Cleaner Outlet Duct Replacement.