Diesel Data: Automotive Repair

Test 2 - Spark at Plug Testing



SPARK AT PLUG CHECK




1. Connect a spark tester between spark plug wire (plug end) and ground, CRANK engine, repeat on all spark plug wires.
2. Does spark jump at each wire? If spark jumps at each plug wire and the engine runs when all wires are attached to plugs check ignition secondary output.
If spark jumps at each plug wire and the engine does not run when all wires are attached to plugs, malfunctioning plugs could be the cause.
If there is no spark at any of the spark plug wires check coil output.