Misfire Under Load (Bad Plugs, Wires or Short to Ground) Pinpoint Test G

13-158 Ignition Systems, Timing Procedures and Diagnostics


3.0L SEFI SHO and 3.8L SEFI SC DIS


Misfire Under Load

Pinpoint Test G

(Bad Plugs, Wires or Short to Ground)


PRELIMINARY NOTES

The engine analyzer is used to diagnose problems in the secondary side of the ignition system.

CHECKOUT

^ Visually inspect the engine compartment to ensure all vacuum hoses and spark plug wires are properly routed and securely connected.

^ Examine all wiring harnesses and connectors for insulation damage, burned, overheated, loose or broken conditions.

^ Be certain the battery is fully charged.

^ All accessories should be off during diagnosis.

EQUIPMENT

Obtain the following test equipment or an equivalent:

^ DIS Adapter Rotunda 007-00044.

^ Engine Analyzer, Rotunda 002-00550.




Ignition Systems, Timing Procedures and Diagnostics


13-159


3.0L SEFI SHO and 3.8L SEFI SC DIS


Misfire Under Load

Pinpoint Test G

(Bad Plugs, Wires or Short to Ground)


NOTE: If this portion of the diagnostic procedure is to provide accurate results, it is essential that the calibration of your engine analyzer be maintained. Refer to your equipment manual. If this is not available, an estimate of the calibration can be made by connecting the spark tester (D81P-6666-A or equivalent) to a properly operating ignition system and measuring the firing voltage of the spark tester only. Do not include the firing voltage of the rotor-to-cap gap. The spark tester firing voltage should be approximately 28 KV.




13-160 Ignition Systems, Timing Procedures and Diagnostics


3.0L SEFI SHO and 3.8L SEFI SC DIS


Misfire Under Load

Pinpoint Test G

(Bad Plugs, Wires or Short to Ground)




Ignition Systems, Timing Procedures and Diagnostics 13-161


3.0L SEFI SHO and 3.8L SEFI SC DIS


Misfire Under Load

Pinpoint Test G

(Bad Plugs, Wires or Short to Ground)