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Home >> Chevrolet >> 2004 >> Monte Carlo LS >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System 3.4L (Introduction) >> Repair Instructions >> Spark Plug Replacement >> Installation Procedure
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Installation Procedure

NOTE: 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 plugs to the specifications. Refer to Ignition System Specifications .
  2. NOTE: 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.
  3. Install the spark plugs to the engine.

    Tighten: 

    • If installing the spark plugs to a new cylinder head tighten the plugs to 20 N.m (15 lb ft).
    • If installing the spark plugs to an existing cylinder head tighten the plugs to 15 N.m (11 lb ft).

  4. Install the spark plug wires to the spark plugs. Refer to Spark Plug Wire Replacement .
  5. Release the J 41131  and return the engine to the original position.
  6. Install the engine mount struts. Refer to Engine Mount Strut Replacement - Left and Engine Mount Strut Replacement - Right in Engine Mechanical - 3.4L.
  7. Fig 1: Identifying Spark Plug & Wire
    GM47610Courtesy of GENERAL MOTORS CORP.