DIESELING/FALSE CODE 53 NEW PROM AVAILABLE

Models Affected: 1984 3.0L Centurys with 125C Transmission (VIN Code E)

A few 1984 Centurys with VIN's lower than ED438182 produced at Doraville and E6471905 at Oklahoma City Plants were produced with a PROM calibration that could possibly have the following conditions:

Engine diesels after ignition is turned off.

Service engine soon light on with code 53.

Deceleration periods of longer than 10 seconds will in some cases set a false code 53.

If a code 53 is stored in memory and use of trouble code chart 53 indicates no problem found, or the condition no longer exists, the VIN should be checked and if it is below the breakpoints listed above, a new PROM listed below should be ordered from WDDGM in the normal manner and installed.

NEW PROM BROADCAST CODE REPLACES -------- -------------- --------- Federal 16042776 DPY 16037602

California 16042782 DPZ 16037607

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.