Fuel System - Line Knock/Rattle

88pontiac07

Bulletin Number: 88-6-46
Reference Number: 836516
Publish Date: 5/88
Subject: FUEL LINE KNOCK/RATTLE


Models

Affected: 1988 GRAND PRIX WITH AUTOMATIC TRANSMISSION (RPO MD9/ME9)



Some 1988 Grand Prix vehicles with automatic transmissions (RPO MD9/ ME9), assembled prior to VIN JF216305, may exhibit a light hammering/ rattle type noise audible after a cold start at low ambient temperatures.

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, following applicable shop manual procedures, of a new fuel return hose and stand-pipe assembly, P/N 10114735, which will reposition stand-pipe in a upward vertical position.
NOTICE: THE EXISTING AND NEW FUEL RETURN HOSE ASSEMBLIES ARE FORMED PARTS. ATTEMPTING TO INVERT THE STAND-PIPE ON THE EXISTING PART BY TWISTING THE HOSE MAY ADVERSELY AFFECT ENGINE OPERATION AND/OR HOSE INTEGRITY.
Use applicable Labor Operation Number and Time..