Spark Plug: Removal

CAUTION: If equipped with a 4.7L H.O. (High-Output) engine, never substitute the original platinum tipped spark plug with a different part number. Serious engine damage may result.

On the 4.0L 6-cylinder engine, the spark plugs are located below the coil rail assembly. On the 4.7L V-8 engine, each individual spark plug is located under each ignition coil.

4.0L 6-Cylinder Engine: Prior to removing spark plug, spray compressed air around spark plug hole and area around spark plug. This will help prevent foreign material from entering combustion chamber.
4.7L V-8 Engine: Prior to removing spark plug, spray compressed air around base of ignition coil at cylinder head. This will help prevent foreign material from entering combustion chamber.
On the 4.0L engine the coil rail assembly must be removed to gain access to any/all spark plug. Refer to REMOVAL . On the 4.7L V-8 engine each individual ignition coil must be removed to gain access to each spark plug. Refer to REMOVAL .
Remove spark plug from cylinder head using a quality socket with a rubber or foam insert. If equipped with a 4.7L V-8 engine, also check condition of coil O-ring and replace as necessary.
Inspect spark plug condition. Refer to DIAGNOSIS AND TESTING - SPARK PLUG CONDITIONS .