STUMBLING BAD AROUND 45,WILL STILL STUMBLE AROUND AT 75 OR 80

1998 CHEVROLET TRUCK
350,000 MILES • 5.7L • V8 • 4WD • AUTOMATIC
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JEHANEY1946
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  • 1 POST
HAVE REP.LACED DISTRIBUTOR,ELECTRONIC SPARK CONTROL. CHECKED TPS,.REPLACED FUEL INJECTORS,DID INJECTOR BALANCE TEST,FUEL PRESSURE TEST
DID A MANUAL RELEARN/ PULLED FUEL PUMP RELAY.STILL RUNS.CHECKED ALL GROUNDS.



Jul 1, 2015 at 10:13 AM
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HMAC300
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are there any codes and what was fuel pressure? did fuel pressure hold at least 10 psi after shutdown?
Jul 1, 2015 at 10:23 AM
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THIS IS MIKE
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JEHANEY1946
July 2, 2015.

55 to 57 pounds yes hold pressure within 10 pounds also have installed new a/c plugs and wires, also put a data logger on it and it has no miss. Will stumble and rpm doesn't change.
Jul 2, 2015 at 1:34 PM
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HMAC300
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fuel pressure should be 60-66 psi with 60 being minimum. looks like it needs a fuel pump
Jul 2, 2015 at 5:08 PM