Ignition System

Remove secondary wire from distributor center tower. Hold end of wire approximately 3/8" from a good engine ground. Crank engine and check for a bright blue spark at gap. See Fig 1 .

Fig 1: Testing Ignition System for Spark Hold end of wire approximately 3/8" from ground.
If spark does not occur, proceed to step 4). If spark does occur, slowly move secondary wire away from ground, checking for arcing at coil tower. If arcing occurs, replace ignition coil.
If spark was good and there was no arcing at coil tower, secondary voltage is good. Check distributor rotor and cap for damage, as well as, secondary wires and spark plugs. If all components are okay, check fuel system or check for mechanical damage to engine components.
If in step 2 spark was weak, not constant, or there was no sparking, turn ignition switch "ON". Connect positive voltmeter lead to negative terminal of ignition coil. Connect negative lead to a good ground. Voltage reading should be within 1 volt of battery voltage.
If voltage is within 1 volt of battery voltage, proceed to step 6. If reading is less than 3 volts, the distributor is defective. If there is no voltage indicated, check for open circuit in ignition coil or wiring harnesses.
If battery voltage was indicated in step 4, hold coil secondary wire about 3/8" from a good ground. Using a special jumper wire assembly, momentarily touch ignition coil negative terminal to ground See Fig 2 . A spark should result.

Fig 2: Special Ignition System Jumper Wire Assembly
If spark results, but engine does not start, proceed to step 9. If there was no spark, check for voltage at positive terminal of ignition coil with ignition switch on (voltmeter positive lead to positive terminal, negative lead to ground). Reading should be at least 12 volts.
If proper voltage is read, ignition coil is defective and must be replaced. If voltage was not to specifications, check wiring back to battery.
If in step 6 a spark was produced, but vehicle will not start, replace distributor.