fuel line replaced and fuel pump line reconnected. no fuel

[Ozark Lee]

I think I may have misread your earlier post on the FPR itself. If you are blowing on the vacuum line port it should hold pressure and feel blocked. I'm not sure if the FPR ever completely closes off from the fuel rail to the return line ports since that would result in a very rapid increase in fuel pressure on the rail. I don't know what kind of blowing pressure your should expect with no vacuum on the control port - I have never gotten that far into the weeds with a FPR and I surely can't exhale with a pressure of 43 PSI.

The other place that will cause the fuel pressure to immediately drop to zero is a bad check valve in the fuel pump housing but that normally just results in hard starts.

I am leaning away from the injectors since they would dump a metric ton of fuel into the intake manifold if the pressure drops that quickly.

I think the way I would go after this is to use a pair of vice grips to pinch and block the fuel return line and see what happens then. If it holds pressure it would mean a bad FPR if it still drops as rapidly as you describe from your earlier test it would point to a bad check valve.

The check valve can't really be repaired on the OEM module if it is bad but an external check valve can be installed in the fuel supply line if that is the problem.

...Lee

[luckyirish7]

I used a vice grip to plug the return line coming out of the FPR on the top of it. I then turned off the car and check the psi. I still got 0 PSI but a tiny amount couple drops of fuel came out. I dont know if that means anything but normally NOTHING comes out when this test is peformed. I did the test twice in case i didn't block of the hose well enough, both times 0psi. Would that mean I need to put an external check valve on?

[Ozark Lee]

I used a vice grip to plug the return line coming out of the FPR on the top of it. I then turned off the car and check the psi. I still got 0 PSI but a tiny amount couple drops of fuel came out. I dont know if that means anything but normally NOTHING comes out when this test is peformed. I did the test twice in case i didn't block of the hose well enough, both times 0psi. Would that mean I need to put an external check valve on?

I obviously can't see the car but from what your describe the problem is likely indeed with the check valve. Blocking off the fuel return line takes the FPR out of the loop so given that the problem continues the next logical place is the fuel pump check valve itself.

I don't have a reliable source for the add on check valves but I do believe I remember member JRL saying that he had a vendor.

...Lee

[luckyirish7]

I have finally got to the junk yard. I bought a used fuel pump and two new fuel lines since I spliced the one going into the fuel filter to try an external check valve. I lowered the fuel tank just enough to get the new fuel line in and think I pinched it off when i put the tank back in place. I am getting no fuel now it seems. The problem I found was the hose on the fuel pump in the tank had come off on one side. I reconnected it and then tightened down the clamp. My question is do you think this is what has caused all my fuel problems? I am going to lower the tank again tomorrow and try to get the hose in a position to where its not cutting off the gas. The picture below shows the pump and where it was disconnected. I will also add a picture of the line I replaced.

[luckyirish7]

This is the fuel line that I replaced. The first one got pinched and maybe broke so I put another one on and made sure no obstruction. Yet again no fuel. Here is the part I replaced.

[luckyirish7]

The problem is fixed. car runs good. I accidentally switched the lines on the fuel pump! All good now!

[falconbrother]

Did you ever figure out why the 5/16 check valve wouldn't fit in the fuel line?