LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Jeep >> 2004 >> Liberty Limited, 4WD, Part Time >> Repair and Diagnosis >> Engine Performance >> Tune-Up >> Ignition System >> Spark Plug >> Installation >> 3.7L
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Spark Plug: Installation: 3.7L

Special care should be taken when installing spark plugs into the cylinder head spark plug wells. Be sure the plugs do not drop into the plug wells as electrodes can be damaged.

Always tighten spark plugs to the specified torque. Over tightening can cause distortion resulting in a change in the spark plug gap or a cracked porcelain insulator.

  1. Start the spark plug into the cylinder head by hand to avoid cross threading.
  2. Tighten spark plugs. Refer to TORQUE - IGNITION SYSTEM .
  3. Before installing coil(s), check condition of coil o-ring and replace as necessary. To aid in coil installation, apply silicone to coil o-ring.
  4. Install ignition coil(s). Refer to IGNITION COIL .