Some 1991 DeVilles and Fleetwoods (start of production through M4305189) may experience excess air from the side window defog or defrost creating a drafty climate from the E or an air "rush" noise from the HVAC outlets caused by the blower speed remaining on high speed for an extended period while set in "auto" mode.
------------ 1. Inspect "Cadillac" script located on the instrument panel above the glove box door.
2. If script is recessed or flush with the instrument panel, remove and replace with P/N 25602888.
3. Install new PROM, P/N 16164048.
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.