Spark Plug Troubleshooting

CONDITION	ACTION
Engine runs rough or will not run	Check the ignition wires or coil packs for proper connection to the spark plugs. Check the ignition wires or coil packs for proper connection to cylinders.
There is a loud hissing noise	One or more spark plugs have been improperly tightened – re-check. One or more spark plugs may have double washers – re-check. Spark plug may have been cross-threaded – re-install.
There is a very loud clicking or tapping noise	A foreign object may have fallen into one of the cylinders. If the noise persists, DO NOT DRIVE THE VEHICLE – have it towed to your Service Department for diagnosis and repair.
Engine has poor performance, runs hot or overheats	The incorrect plugs may have been installed – re-check. The spark plug gap may be incorrect – re-check. One or more ignition wires may have been damaged. DO NOT DRIVE THE VEHICLE if the engine overheats.