Remove the spark plugs and examine them for burned electrodes and fouled, cracked or broken porcelain insulators. Keep plugs arranged in the order in which they were removed from the engine. A single plug displaying an abnormal condition indicates that a problem exists in the corresponding cylinder. Spark plugs that have low mileage may be cleaned and reused if not otherwise defective, carbon or oil fouled.
Removal & Installation
Each individual spark plug is located under each ignition coil. The ignition coil must be removed in order to access the spark plug.
- Remove the ignition coil.
- Remove the spark plug from the cylinder using a spark plug socket with the appropriate rubber insert.
Start the spark plug by hand and then tighten as follows:
- 3.7L & 4.7L Engines: 20 ft. lbs. (27 Nm).
- 5.7L Engine: 13 ft. lbs. (18 Nm).
- Install the ignition coil.