Mechanics

FUEL PRESSURE / FUEL GAUGE

1988 Ford Mustang

1988 Ford Mustang V8 Automatic

PART 1 ( fuel pressure )
this ia a stock 5.0 HO. I have 30 psi of fuel at idle. It will increase to 40 psi if I remove the vacuum from the fuel regulator and it does go back to 30 psi when vacuum is replaced. If I close/ pinch of the fuel return from fuel regulator to the tank my fuel pressure does not increase ( I beleive it should ). With the fuel gauge still attached to the fuel line I drive the car and the fuel pressure drops down to 20 psi and lower. This is my problem, under mid to heavy acceloration I get popping / backfire out of the throttle body. I noticed it is only when the fuel pressure is low. By the way this is with a new fuel pump. ( I think I have a defective fuel pump ). And I beleive the fuel pressure should rise under acceloration. Can someone confirm this?

PART 2 ( fuel guage )
the gauge did not ( always read full ). I got a boneyard sending unit and it tested 12 ohms full and 74 ohms empty ( I beleive this to be the correct specs ). Once the tank was back up and filled with gas, the dash gauge reads closer to empty with the more gas I put in. Can anyone help here?

IS IT POSIABLE THE TWO HAVE ANYTHING RELATED IN A SHORTING OUT / LOSE OF POWER KIND OF WAY?
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Goldroads
November 9, 2008.



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