Attach the spark plug to a spark plug tester, then connect the tester to the ignition wire. Start the engine and observe the ...

Use a spark tester to check the ignition coil. Plug the tester into the coil. Attach the ground wire. Plug in the coil connector. Adjust the spark gap to the correct measurement. Start the engine.

How to test a spark plug Although this is something you can certainly leave up to the professionals, it’s also simple enough to do at home.