TRACE DETONATION V8-6-4 ENGINE 'CONDITIONS'CONSIDERED NORMAL

GR.6D DETONATION V8-6-4 ENGINES TRACE DETONATION ON SOME V8-6-4 EQUIPPED VEHICLES SHOULD BE CONSIDERED NORMAL UNDER THE FOLLOWING CONDITIONS: A.HEAVY WIDE-OPEN THROTTLE ACCELERATIONS FROM A STOP. B.DURING CYLINDER MODE CHANGES (8-6, 8-4, ETC.). FACTORS THAT CAN AGGRAVATE DETONATION ARE AS FOLLOWS: A.BASIC ENGINE TIMING NOT PROPERLY SET. B.A RESTRICTED VACUUM SIGNAL TO THE EGR VALVE CAUSE BY PINCHED OR KINKED HOSES.

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.