GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2000 🢒 GL7 (Export) 🢒 Engine 🢒 Engine Controls - 3.0L (LW9) 🢒 Spark Plug Replacement

Removal Procedure

Notice: 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. Turn the ignition OFF.
  2. If you are replacing the engine right bank (rear) spark plugs, perform the following steps:
    3. 2.1. Remove the windshield wiper module cover. Refer to Wiper Motor Cover Replacement in Wipers Washer System.
    2.2. Rotate the engine for service access. Refer to Rotating the Engine for Service Access in Engine Mechanical.

    Object Number: 47610 Size: SH
  3. Remove the spark plug wire(s) from the spark plug(s). Refer to Spark Plug Wire Harness Replacement .
  4. Remove the spark plug(s) from the engine.

Installation Procedure

    Notice: 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.

  1. Gap the spark plug(s) to the specifications. Refer to Spark Plug Usage.

    2. Object Number: 47610 Size: SH

    Notice: Be sure plug threads smoothly into cylinder head and is fully seated. Use a thread chaser if necessary to clean threads in cylinder head. Cross-threading or failing to fully seat spark plug can cause overheating of plug, exhaust blow-by, or thread damage. Follow the recommended torque specifications carefully. Over or under-tightening can also cause severe damage to engine or spark plug.

  2. Install the spark plug(s) to the engine.

    3. Tighten
    Tighten the spark plug(s) to 15 N·m (11 lb ft).

  3. Install the spark plug wire(s) to the spark plug(s). Refer to Spark Plug Wire Harness Replacement .
  4. If you are replacing the engine right bank (rear) spark plugs, perform the following steps:
    5. 4.1. Return the engine to the proper position. Refer to Rotating the Engine for Service Access in Engine Mechanical.
    4.2. Install the windshield wiper module cover. Refer to Wiper Motor Cover Replacement in Wipers Washer System.