For 1990-2009 cars

# HEI MODULE CODE 42 INCORRECT HEI MODULE

WHEN REPLACING AN H.E.I. MODULE, BE SURE THAT THE CORRECT PART NUMBER IS BEING INSTALLED. 1981 AND 1982 ARE NOT INTERCHANGEABLE. THE CORRECT MODULE PART NUMBERS ARE: 1981 - 1978617 1982 - 1976908 NOTE: THERE MAY BE ADDITIONAL PART NUMBERS OTHER THAN THOSE LISTED ABOVE. MAKE SURE THE PART NUMBER ON THE PART AGREES WITH THE NUMBER ON THE BOX IT CAME IN. SOME OF THE PARTS ORDERING SYSTEMS DEALERS UTILIZE WILL MIX THE PART NUMBERS AND SHIP THE INCORRECT H.E.I. MODULE. THIS IS BEING ADDRESSED AND CORRECTED. IF A 1981 H.E.I. MODULE IS INSTALLED IN A 1982 SYSTEM, THE CHECK ENGINE LIGHT WILL COME ON AND CODE 42 WILL BE STORED.

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.