GM Service Manual Online
For 1990-2009 cars only

ENGINE RUN-ON WHEN IGN. SWITCH IS TURNED OFF

VEHICLES AFFECTED: 1988-1989 C-H MODELS WITH 3800 ENGINE

If a condition is encountered of engine run-on with the ignition switch turned off on the above models with 3800 engines, proceed with the following correction.

Inspect the MAF/TPS wiring branch at the back of the generator. In some cases the branch was found wedged below the "B-plus" (BAT Terminal) bolt on the back of the generator (see attached figures).

Thus the "B-plus" (BAT Terminal) bolt could be aligned with the conduit slit and contacted the wiring directly eventually rubbing through. The wire contacted would be the ignition feed to the mass air flow sensor (pink with black stripe, CKT439) which could back-fed the ignition switch allowing the engine to continue running.

This condition can be corrected by removing the branch from the underside of the "B-plus" (BAT Terminal) connection, repairing as necessary, and routing it above the B-plus (BAT Terminal).


Object Number: 84373  Size: FS

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.