Engine - Fuel Line Knock After Cold Start

91buick01

Bulletin 90-6E-22


Date Feb. '91


Ref. No. 90-214-6E


Corp. Ref. No. 006506


SUBJECT: FUEL LINE KNOCK/RATTLE (NEW FUEL PRESSURE REGULATOR)


MODELS AFFECTED: 1989-90 CENTURY AND SKYLARK VEHICLES EQUIPPED WITH 3300 ENGINE (VIN N)


Some 1989-90 Century and Skylark vehicles equipped with the 3300 engine (VIN N) may exhibit a light knock/rattle type noise, audible after a cold start at ambient temperatures below 40~ Fahrenheit.


The noise may be audible either in or outside of the vehicle from start-up until the engine is up to normal operating temperatures.


This condition is caused by fuel system pulsations generated by fuel injector operation causing a hydraulic hammering in the chassis fuel pipes.


Vehicles exhibiting this condition may be repaired by installing a new design fuel pressure regulator, Part Number 17112611. The new Fuel Pressure Regulator has a reduced seat orifice and the orifice chamfer has been removed.


IMPORTANT: THE NEW FUEL PRESSURE REGULATOR, PART NUMBER 17112611 WILL ALSO BE THE NEW SERVICE REPLACEMENT REGULATOR FOR THE 1989-90 3300 ENGINE (VIN N), REPLACING PART NUMBER 17112117.

Parts are currently available from GMSPO.

WARRANTY INFORMATION:

Use applicable "J" operation for replacement of Fuel Pressure Regulator.