REAR MAIN OIL LEAK DIAGNOSIS

VEHICLES AFFECTED: 1985-87 M VANS WITH THE 2.5L (VIN CODE E) OR 4.3L (VIN CODE Z) TBI ENGINES

Some 1985-87 M vans with TBI engines may experience a stall or no start condition. This condition may be diagnosed as an inoperative intank fuel pump. Inspection of the intank fuel pump may indicate that it has become dislodged (laying in the bottom of the fuel tank) from the fuel sender.

A dislodged fuel pump condition may be caused by the intank fuel reservoir (plastic), which surrounds the fuel pump, coming loose inside the fuel tank and dislodging the fuel pump from the fuel sender. The reservoir can be checked by inserting a 24 inch long 3/8 inch drive extension (or similar) into the tank through the fuel sender opening and pushing (fore and aft) on the reservoir.

The reservoir should not move. Do not pry against the fuel sender opening as this could result in damage to the tank. If this condition is encountered, the fuel tank assembly must be replaced and at the same time, the intank fuel pump must be repaired or replaced.

Parts Information

Part Number Description Quantity

14056821 Tank - 17 Gallon 1 14056823 Tank - 27 Gallon 1

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.