SECONDARY SPARK TEST
See Figure 1
The best way to perform this procedure is to use a spark tester (available at most automotive parts stores). Two types of spark testers are commonly available:
If a secondary spark tester is not available, a regular spark plug may be used.
- Disconnect a spark plug wire at the spark plug end.
- Connect the plug wire to the spark tester and ground the tester to an appropriate location on the engine.
- Crank the engine and check for spark at the tester.
- If spark exists at the tester, the ignition system is functioning properly.
- If spark does not exist at the spark plug wire, remove the distributor cap and check that the rotor is turning when the engine is cranked.
- If the rotor is not turning, a problem exists in the engine either in the engine or distributor.
- If the rotor is turning, perform the spark test again using the ignition coil wire.
- If spark does not exist at the ignition coil wire, test the ignition coil, power transistor and related wiring. Repair or replace components as necessary.