Performance Issues Due to Faulty ECM Grounds at Front of Engine on Cadillac Fleetwood

The engine control module (ECM) electrical grounds on the front of the engine block may have high resistance causing a rough running engine or stalling condition.

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Average mileage: 140,000 (140,000–140,000)
5 model years affected: 1990, 1991, 1992, 1993, more1994
6 people reported this problem
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1991 Cadillac Fleetwood 140,000 mi,
Runs fine, the all of a sudden, begins to run rough, rough idle, stalls when stopped or in turns, check engine light comes on only when on highway, sevice soon light on sometimes. 2 different mechanics couldn't find problem.