Cherokee 4WD L6-4.0L VIN S (1998)
Spark Plug: Service and Repair
REMOVAL
Cable Removal
1. Always remove spark plug or ignition coil cables by grasping at the cable boot. Turn the cable boot 1/2 turn and pull straight back in a steady
motion. Never pull directly on the cable. Internal damage to cable will result.
2. Prior to removing the spark plug, spray compressed air around the spark plug hole and the area around the spark plug. This will help prevent
foreign material from entering the combustion chamber.
3. Remove the spark plug using a quality socket with a rubber or foam insert.
4. Inspect the spark plug condition. Refer to Spark Plugs in the Diagnostics/Service Procedures.
INSTALLATION
Always tighten spark plugs to the specified torque. Over tightening can cause distortion. This may result in a change in the spark plug gap, or a
cracked porcelain insulator.
When replacing the spark plug and ignition coil cables, route the cables correctly and secure them in the appropriate retainers. Failure to route the
cables properly can cause the radio to reproduce ignition noise. It could cause cross ignition of the spark plugs, or short circuit the cables to ground.
1. Start the spark plug into the cylinder head by hand to avoid cross threading.
2. Tighten the spark plugs to 35-41 N.m (26-30 ft lbs.) torque.
3. Install spark plug cables over spark plugs.