Ignition System
- Check for proper ignition voltage output using the following steps:
- Clip Spark Tester (J 26792) to engine ground.
- Connect one end of a spark plug wire to the spark tester. Connect the other end of the spark plug wire to the coil being tested.
- Connect another spark plug wire between the remaining tower of the coil being tested and ground.
- Crank the engine while observing the spark tester. A crisp Blue spark should be observed.
- Repeat procedure for each coil.
- If spark is not present at the coils, inspect for the following conditions:
- Coils
- Cracks, carbon tracking/arcing, or a secondary resistance value outside the specified coil resistance range of 5-8 k/ohms.
- Spark Plug Wires
- Signs of arcing/cross firing, cracks, carbon tracking, plug boot damage, pinched, improper routing, or a resistance value outside the specified range of 3000 ohms per foot (9840 ohms per meter) or 600 ohms per foot (1968 ohms per meter) for Police models. Spraying the secondary ignition wires with a light mist of water may help locate an intermittent condition. Ignition components will arc to ground when a secondary component is faulty.
- Defective Module
- See ELECTRONIC IGNITION SYSTEM DIAGNOSIS
under IGNITION SYSTEMS in BASIC DIAGNOSTIC PROCEDURES - 3.8L BONNEVILLE, GRAND PRIX, IMPALA, LESABRE, MONTE CARLO, PARK AVENUE & REGAL.
- Ignition System Wiring
- Loose ignition module feed or ground connection, or damaged system wiring.
- Remove spark plugs and inspect for fouling, cracks, wear, improper gap, burned or damaged electrodes and for improper heat range or reach.
- If spark plugs are gas or oil fouled, the cause of the fouling must be determined before replacing the spark plugs.