Symptom Related Diagnostic Procedures

Spark Plug Test:

1. Remove the spark plug and connect to the spark plug cable.
2. Ground the spark plug outer electrode (body) and crank the engine.
Check to be sure that there is an electrical discharge between the electrodes at this time, and there is no defective insulation.
3. Remove the spark plug from the boot and usually inspect it for cracks in its insulation.
4. Replace the spark plug if it has a weak spark and/or detective insulation.