Century V6-173 2.8L VIN W FI (1987)
Fuel Supply Line: Customer Interest
Fuel System - Line Noise (Knock/Hammering)
Bulletin:
88-6C-1
Date:
Nov., '87
Ref. No.: 88-029-6C
Corp. Ref. No.: 836303
SUBJECT:
FUEL LINE "KNOCK/HAMMERING" NOISE
MODELS AFFECTED: 1987-88 CENTURYS WITH THE LB6 2.8L V-6 ENGINE (VIN CODE W)
Some 1987-88 Centurys with 2.8L MPFI engines may exhibit a light hammering/knocking type noise audible in the vehicle passenger compartment. The
noise condition may be noted in a cold start mode, and/or warm stabilized mode and is most apparent at engine idle.
This condition may be caused by pressure pulsations in the fuel system generated by fuel injector operation, resulting in hydraulic hammering in chassis
fuel pipes.
Vehicles exhibiting this condition may be repaired by installation of the part(s) noted below by model year, following the service procedure in this
bulletin.
PART REQUIREMENT BY MODEL YEAR
PART NUMBER
PART DESCRIPTION
1987
1988
10115809
Fuel Feed Pipe Expansion
1
1
Chamber Assembly
10093228
Fuel Return Hose Stand
1
--
Pipe Assembly
Service Procedure:
1.
Disconnect negative battery cable and remove fuel tank filler cap.
2.
Relieve pressure in fuel system following shop manual procedure.
3.
Disconnect fuel feed and return hoses at engine fuel feed and return pipes utilizing backup wrench on fittings.
4.
On 1987 model vehicles only, disconnect fuel return hose at chassis fuel return pipe utilizing backup wrench on fitting and discard hose assembly.
5.
Remove bolt securing engine fuel feed and return pipe bracket at cylinder head.
6.
Remove oil fill cap and disconnect vacuum line and the idle air control valve electrical connector at the throttle body.
7.
Disconnect fuel return pipe and then fuel feed pipe at fuel rail fittings utilizing backup wrench.
8.
Position pipes to gain access to bolt securing pipe clip to engine bracket and remove bolt.
9.
Remove feed pipe from clip and discard.
10.
Torque fuel rail feed and return fittings to 20-26 N-m.