Testing for Spark at Coil

Spark Tester:

1. Disconnect #1 ignition wire at the spark plug.
2. Install a spark tester into the end of the spark plug boot.
3. Have an assistant crank the engine over and check for spark at the tester.
4. Repeat this process at each spark plug.
- If any cylinder does not show spark, proceed to secondary component tests.
- If ALL secondary components show no spark, test components individually.
- If all cylinders test O.K., inspect for fouled spark plugs and clean or replace as necessary.
5. If no faults are found in the above tests, proceed to Computers and Control Systems for further diagnosis.