For 1990-2009 cars

# CLEAN PORT FUEL INJECTORS GASOLINE ADDITIVES

#### MODELS AFFECTED: ALL MODELS WITH PORT FUEL INJECTORS

This bulletin supersedes Dealer Service Information Bulletin 87-I-2, which should be destroyed.

Some owners of vehicles with multi-port injection systems may have experienced impaired driveability resulting from deposits forming on fuel injectors. Symptoms include a rough idle and decreased acceleration. When the problem was first recognized, few gasolines contained detergent additives which could prevent deposit buildup, and even fewer could remove deposits from injectors.

About a year ago, General Motors and other auto companies asked gasoline suppliers to provide gasolines containing suffficient concentrations of appropriate detergents to prevent port-fuel injector deposits.

The response to auto industry requests has been very encouraging. It appears that all major brands are treated with detergent additives, and that many independent brands are now or soon will be treated. This includes brands selling gasoline containing ethanol, for which the ethanol has been treated with a detergent additive.

Because the number of brands treated with detergents is becoming so extensive, General Motors is no longer publishing a list of brands advertised to contain the needed detergents. Instead, customers should be urged to purchase fuel from any gasoline marketer who states, at the point of purchase or through media advertising, that the gasoline contains sufficient detergent additives to prevent port fuel injector deposits or remove them from fouled injectors. Customers properly informed by claims of gasoline suppliers or marketers will be in a position to prevent the unnecessary fouling which may result from use of a gasoline with ineffective or no detergent additives. While these claims are not based on data generated by General Motors, we have no reason to doubt their truth.

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.