joewom

Ok. I am slowly working thru this fuel pressure issue as life has been busy. I am thinking for starters that the lines are way to complicated in my current setup. Links for pics are below. Can I simplify this set up? Fuel line comes in to the fuel rail say front drivers side connect a line to connect the back of rails and the return line hook up to the front passenger side? Could all these lines and Y's be causing fuel pressure loss. Or is this set up good? All comments are appreciated!

https://www.dropbox.com/s/vblow8ffvr...51.31.jpg?dl=0

https://www.dropbox.com/s/7e95ooqjs5...18.01.jpg?dl=0

chris308

you'd probably get quicker replies in the FI section.

neutron82

it definitely is kind of a mess and could be cleaned up... what kind of pump are you running?... in tank or secondary?... are the lines from the tank stock or has it been tapped with a bulkhead, etc?... I'm wondering why whoever put that system together didn't hook up the vacuum line to the regulator and boost reference it... that way your pressure will rise under boost instead of drop... where are the lines on the passenger side going?... the pic doesn't clearly show where they are hooked up

joewom

It's a walboro 255 in tank with a A&a secondary. I just got done cleaning it up. I don't know why they didn't boost reference it or why he would split the fuel coming into the rails into two line coming in the front of the rails then the two lines coming out the back into y back to a single line to the regulator. I changed it to the fuel coming in goes to the driver side front the rear is tied in together and the return line goes out the passenger front to the regulator. Idles strong at 59psi but as soon as I give some gas drops to low 50s and when get a little more drops in the 40s. Once at 2psi boost the secondary kicks on and it pegs at 62psi all the way up to 8psi. I think the in tank pump is going.

neutron82

if you ran only one line to your regulator did you plug the other side and if not where is that other line going?... the way you described that you cleaned it up you could plug the other end of your regulator... you might as well hook up the vacuum line and have the tune cleaned up

joewom

The other side is going back to the tank. I am going to do all that but first I think I am going to replace the fuel pump in the tank. I don't like the drop in pressure.

neutron82

does your regulator not have a fitting on the bottom, that's the line that should go back to the tank... like I said it's hard to tell where it's going on your pics... it looks like the regulator is tied into 2 lines with a "y" but doesn't show where they are tied back in... it looks like one goes to the passenger rear rail, what about the other one?

4DRUSH

joewom

Yes it does and from what I can tell the line coming out the bottom of the regulator is going back to the tank. The other was going back to the driver side rear rail.

neutron82

ok well it should work that way it's just cluttered, not sure if that would create the problem you are having though... I would still hook up vacuum to the regulator and have the tune looked at and tweaked if necessary... do you have any idea when the secondary pump kicks on?... your in tank pump may not be going bad but if the secondary pump is coming on too late your tank pump could be maxing out before that switchover... might check to see if you have an adjustable hobbs switch and see where it is set... I am no tuner so I couldn't tell you what to do other than have them look at the tune and tell you where you need to set it to come on

joewom

I will hook it up. I secondary kicks on at 2psi. But I am seeing 5psi drop just touching the gas pedal. If I go WOT it gets to 40psi before 2psi of boost. Once the secondary kicks on its solid at 62psi all the way thru. If I have anything under 1/2 tank its worse. And 1/4 of tank its idling at 40 to 45psi. Which is why I am thinking fuel pump.

And thank you for your replies!! I will add a picture of the work I did to simplify the setup.

joewom

After Picture.

rclinton

Couldn't bring up your first two pics because I'm at work, so I cant help with the plumbing, but I will throw this out. Check that you have a early style fuel filter (the one without the fuel regulator in it. I am running about the same HP as you are and I am running an LPE in tank pump, stock fuel rails with a regulator and return line with a early style fuel filter. I hold 60 psi throughout.

joewom

Would the only way to find that out be to get to the fuel pump?

neutron82

what year is the car?... up to early 03 the filter should be on the inside frame rail, if you get under the car you should see it on the driver's side near the rear wheel... it should only have one in and one out if it's the 97-98 style filter which you should have with a return style fuel system... also what is the vacuum fitting on your rails for?

joewom

2003 late it has or had the FPS system you know the easy one to get to the fuel pump. Not lol. And that is just a scrhader valve to release fuel pressure or hook up a mechanical fuel pressure gauge.