HARD OR NO START AND/OR DOES NOT MAINTAIN FUEL PRESSURE

MODELS AFFECTED: 1985 CIMARRONS EQUIPPED WITH 2.8L V-6

Some 1985 Cimarrons equipped with the 2.8L V-6 Port Fuel Injected Engine may experience extended engine cranking time, poor driveability, won't stay running, and/or may not maintain fuel rail pressure due to a leaking pulsator.

The Fuel System Diagnosis Procedures, Chart A-7A in Section 6E3 of the Cimarron Service Information Manual, states if the fuel rail does not hold pressure, except while pinching the pressure line flex hose, the problem is either a leaking pump coupling hose or a faulty in-tank pump. In addition, the problem may also be caused by a leaking fuel sender pulsator.

To determine which compornent is causing the pressure line leak down, perform the following procedure:

1. Remove the sending unit assembly from tank.

2. With the fuel pick-up sock still attached, submerge the sender assembly in clean water far enough to completely cover the fuel pump and pulsator.

3. Apply regulated air pressure (not to exceed 20 psi) to the pressure line of the sending unit assembly.

4. Watch for air escaping from around the pulsator or the end of the pump to identify the faulty component.

NOTICE: SENDER MUST NOT BE SUBMERGED IN WATER FOR AN EXTENDED PERIOD OF TIME AND MUST BE DRIED WITH COMPRESSED AIR IMMEDIATELY UPON REMOVAL

5. Replace parts as necessary and recheck.

The new part number for the puisator is 6472359 and is available through GMWDD.

For warranty purposes use labor operation L1200 to replace the pulsator at .8 hours.

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.