GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2009 🢒 Lucerne 🢒 Engine 🢒 Engine Cooling 🢒 Spark Plug Replacement

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.


    Object Number: 1608802 Size: SH
  1. Remove the air cleaner outlet duct, if required. Refer to Air Cleaner Outlet Duct Replacement.
  2. Remove the intake manifold cover, if required. Refer to Intake Manifold Cover Replacement.
  3. Remove the left side spark plug wires from the spark plugs, if required.

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

    5. Object Number: 1587748 Size: SH
  5. Remove the spark plugs.

Installation Procedure

Caution: It is important to check the gap of all new and reconditioned spark plugs before installation. Pre-set gaps may have changed during handling. Use a round wire feeler gauge to be sure of an accurate check, particularly on used plugs. Installing plugs with the wrong gap can cause poor engine performance and may even damage the engine.

    Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 1587748 Size: SH
  1. Gap the NEW spark plugs. Refer to Ignition System Specifications.
  2. Install the spark plugs.

    3. Tighten
    Tighten the plugs to 15 N·m (11 lb ft).


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

    4. Object Number: 1608802 Size: SH
  4. Install the left side spark plug wires to the spark plugs, if required.
  5. Install the intake manifold cover, if required. Refer to Intake Manifold Cover Replacement.
  6. Install the air cleaner outlet duct, if required. Refer to Air Cleaner Outlet Duct Replacement.