DIESEL HARDSTART/LOSS OF POWER ELECTRIC FUEL PUMP INOPERATIVE

MODELS AFFECTED: V-6 Diesels

With an inoperative electric fuel pump, an engine timing shift of about -3 DEG will be experienced. The engine may continue to run; however, some power loss will be experienced, and hard starting may result. If these symptoms exist, make sure the electric fuel pump is working before dynamic timing is checked or reset.

To determine if the electric fuel pump is operating, turn the ignition key to the "on" position and loosen the fuel outlet pipe at the electric fuel pump. If there is pressure, fuel will leak out. This indicates the fuel pump is working.

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.