REDUCED PERFORMANCE ADD ON ELECTRICAL EQUIP. INFORMATION

Model and Year ALL MODELS/YEARS WITH FUEL INJECTED ENGINES

TO: ALL CHEVROLET DEALERS

This cancels and replaces Chevrolet Dealer Service Bulletin 84-167 dated September, 1984 which should be destroyed. This is being reissued to cover all vehicles with fuel injected engines, all years, not only vehicles with VIN Codes P, and 8.

In an effort to prevent customer dissatisfaction concerning engine performance, driveability and/or operation of other vehicle electrical systems due to the addition of equipment, the following information is being provided.

The Electronic Control System and Throttle Body Injection (TBI) engines are designed to work with the electrical system provided in the vehicle. The addition of any electrical or vacuum operated equipment or accessories not offered as original equipment or as a factory approved option may adversely affect the operation of the fuel injection system and the engine performance. Electrical connections should not be made to any of the engine fuel control electrical wiring for a 12 volt source or ground.

Equipment operated by vacuum can also affect engine performance and driveability as this allows unmeasured air (any air source not measured by the mass air flow sensor on vehicles so equipped) to enter the engine, which can affect fuel air mixture ratios.

If the addition of a component affects engine performance, driveability or operation, it is recommended that the custo- mer be advised to disconnect the unit which is creating the condition and refer them to the persons responsible for making such installation.

The addition of any electrical or vacuum operated equipment that results in damage to the engine electronics, or creates driveability problems is not the responsibility of Chevrolet Motor Division. Such repair expense is the responsibility of the persons or company making such installation.

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.