GM Service Manual Online
For 1990-2009 cars only

OIL FILTER CHANGE NOT REQUIRED AS A RESULT OF SPARK PLUG FOUL

OIL FILTER CHANGE REQUIREMENT AS A RESULT OF SPARK PLUG FOULING

Model and Year: ALL MODELS --------------

TO: ALL CHEVROLET DEALERS

Last winter, a number of dealers were found to be changing a large number of engine oil filters. Our investigation revealed that an oil and filter change was being performed in conjunction with a spark plug fouling repair. The concern of the dealer was that the oil had been contaminated by gasoline when the engine failed to start.

Gasoline in the oil will boil off at relatively low temperatures and will have no detrimental effect on engine performance. Changing oil or oil filters as a result of fouled spark plugs is not necessary.

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.