C CAR V6 DRIVEABILITY LESS SENSITIVE ESC MODULE

GR. 6D 1981 C-CAR V-6 DRIVEABILITY 1981 V-6 EQUIPPED DEVILLES AND BROUGHAMS BUILT BEFORE BROADCAST NUMBER 112658 MAY EXHIBIT POOR DRIVEABILITY QUALITIES. THIS CAN BE CAUSED BY THE ELECTRONIC SPARK CONTROL (ESC) SYSTEM SENSING ENGINE VIBRATIONS THAT ARE NOT SPARK KNOCK OR DETONATION RELATED. TO DETERMINE IF THIS MAY THE CAUSE, DISCONNECT THE DETONATION SENSOR CONNECTOR (LOCATED AT THE REAR OF THE ENGINE BLOCK). IF THE DRIVEABILITY IMPROVES, REPLACE THE ESC MODULE, P/N 1224745. ALL MODULES INSTALLED ON AFTER-NUMBER VEHICLES AND THOSE IN GMWDD STOCK HAVE BEEN MODIFIED TO SENSE DETONATION ONLY. THE MODIFIED MODULES CAN BE IDENTIFIED BY A RED OR PURPLE NUMBER 10, 11 OR 12 STAMPED ON THE PART NUMBER LABEL. RETURN REPLACED ESC MODULES TO GMWDD FOR CORE CREDIT.

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.