V 2500 P/U 4WD V8-350 5.7L (1987)
Fuel Supply Line: All Technical Service Bulletins
Fuel Pipe - Vibration Noise At Idle
CHEVROLET NUMBER: 87-T-80
SECTION:
6C - Engine Fuel
DATE:
March, 1987
SUBJECT:
FUEL PIPE VIBRATION NOISE AT IDLE
MODELS:
1987 R/V TRUCKS EQUIPPED WITH 5.0L (VIN CODE H), 5.7L (VIN CODE K), 4.3L
(VIN CODE Z) OR 7.4L (VIN CODE N) ENGINES
Some 1987 R/V models equipped with TBI engines may have a condition where the fuel feed and return pipe assemblies have been mispositioned while
the vehicle was being built. As a result, the pipes contact body sheet metal, causing an unacceptable injector pulse (buzzing) noise inside the truck near
the dash or the floor pan at low idle speeds. This condition can be repaired using the following procedures.
FIGURE 1 - FUEL PIPE FEED INSPECTION
SERVICE PROCEDURES
5.0L OR 5.7L ENGINES
1.
Remove the air cleaner assembly.
2.
Inspect the fuel feed pipe (Figure No. 1) routing. The pipe is routed near an intake manifold vacuum boss on the rear manifold runner. Contact at
this point pushes the pipe into the body dash cowl panel or transmission tunnel. If pipe contact is evident, reposition the pipe away from the
vacuum boss. It should not be necessary
to disconnect or unclip the pipes to reposition them.
3.
Reinstall the air cleaner and retest the truck.
