Ignition System Starting Test
Checking For Spark:
1. Remove coil secondary wire from distributor cap. Hold end of wire about 6mm (1/4-inch) away from a good engine ground. Have a helper crank the engine while you look for a spark at coil secondary wire.
2. If there is a spark at coil secondary wire it must be constant and bright blue in color. If it is, have helper continue to crank engine and while slowly moving coil secondary wire away from ground, look for arcing at the coil tower. If arcing occurs replace coil. If spark is weak or not constant or there is no spark, proceed to the "Failure To Start Test."
3. If spark is good and there is no arcing at the coil tower the ignition system is producing the necessary high secondary voltage. However make sure that this voltage is getting to the spark plugs by checking the distributor rotor, cap, spark plug wires, and spark plugs. If they are okay then the ignition system is not the reason why the engine will not start. It will be necessary to check the fuel system and engine mechanical items.