GM Service Manual Online
For 1990-2009 cars only

SERVICE GUILD: ENGINE MISS/ BACKFIRE/HES. POOR ENG. GROUND

Model and Year: 1987-88 CAVALIER, CORSICA, BERETTA WITH 2.OL (VIN CODE 1) ENGINE

If the engine is diagnosed as having a miss, backfire, or hesitation, then perform the following electric ground check first. Trace back from the battery negative cable to the transaxle. The transaxle electric ground should be secure. Torque the cable/strap to 10-14 N.m (or 7.5 - 10.0 ft. lb.).

A loose ground at this point can cause the direct ignition system (DIS) module to misinterpret it as the crank sensor signal. The DIS could become temporarily out of sync, and this could lead to an engine miss/backfire/hesitation problem.


Object Number: 83551  Size: FS

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