LIGHT HAMMER/RATTLE NOISE (REPL.FUEL FEED HOSE ASSY.)

SUBJECT: LIGHT HAMMER/RATTLE NOISE (REPLACE FUEL FEED HOSE ASSEMBLY)

VEHICLES AFFECTED: 1989-92 "F" MODEL WITH 5.OL OR 5.7L V-8 ENGINE (RPO'S LB9,L98)

CONDITION:

--------- Some 1989-92 F-cars with 5.OL V-8 engines (RPO LB9) or 5.7L V-8 engines (RPO L98) may exhibit a light hammering/rattle type noise audible in the vehicle passenger compartment.

CAUSE:

----- Pressure pulsations in the fuel system, generated by fuel injector operation, causing hydraulic hammering in chassis fuel pipes.

CORRECTION:

---------- Replace existing underhood fuel feed hose with new hose and damper assembly, P/N 10238701, following applicable Service Manual procedures, Section 6C, Engine Fuel and attached illustration.

For vehicles repaired under warranty use:

Labour Operation: L0220 Use applicable Labor Times.

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.