fuel pressure / leak after new fuel pump
#11
Senior Member
You had a sender problem.....why did you replace the pump?
Unfortunately, you need special tools to test the system.....You have plastic lines that have quick connnects near the fuel rail.....you disconnect the fuel lines from the fuel rail.......the special tools are shutoff valves that install between the fuel line and the fuel rail.....install on the supply and return lines....attach a fuel gage to the schraeder valve on the rail......
Turn key to on.....watch gage....turn key off.......fuel pressure should not drop.....if it does, have someone turn the key to on and when max pressure is achieved, CLOSE BOTH VALVES......
If pressure does not hold, check vac line to f/p regulator.....if no fuel present, you have an injector leaking.......
If it holds, open the return......if pressure drops, bad regulator.....
If it still holds, open the supply valve, if pressure drops, there is a leak in the supply line somewhere(where it attaches to the f/p module?), or there is a problem with the check valve in the fuel pump......
I think you have two problems.....naturally one is the drop in fuel pressure when the pump stops.....your other is evap pressure.......all things being equal, if there was no evap leak before replacing the pump and sender, and the gas cap and sea is ok, the only things it can be, are the o-ring seal on top of the tank(pinched/damaged), or the evap that attaches at the top of the module with the other two fuel lines(this has no fuel, so you can't "see" a leak)......
Unfortunately, you need special tools to test the system.....You have plastic lines that have quick connnects near the fuel rail.....you disconnect the fuel lines from the fuel rail.......the special tools are shutoff valves that install between the fuel line and the fuel rail.....install on the supply and return lines....attach a fuel gage to the schraeder valve on the rail......
Turn key to on.....watch gage....turn key off.......fuel pressure should not drop.....if it does, have someone turn the key to on and when max pressure is achieved, CLOSE BOTH VALVES......
If pressure does not hold, check vac line to f/p regulator.....if no fuel present, you have an injector leaking.......
If it holds, open the return......if pressure drops, bad regulator.....
If it still holds, open the supply valve, if pressure drops, there is a leak in the supply line somewhere(where it attaches to the f/p module?), or there is a problem with the check valve in the fuel pump......
I think you have two problems.....naturally one is the drop in fuel pressure when the pump stops.....your other is evap pressure.......all things being equal, if there was no evap leak before replacing the pump and sender, and the gas cap and sea is ok, the only things it can be, are the o-ring seal on top of the tank(pinched/damaged), or the evap that attaches at the top of the module with the other two fuel lines(this has no fuel, so you can't "see" a leak)......
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1johnse2082
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07-25-2014 12:15 PM
mikeblue94
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10-31-2004 03:20 PM