Fuel Pressure Going Down?? Need Help!

[lolwat]

first up new filter BAM!!!!!!!! then if it still drops a pump and check your tank(drain it, check for water etc etc)

[Golberg]

Are you running a stock fuel pressure reg?

[Nikkojoe]

Its still gotta be there (the brown/red one) because thats is for the fpr. Blue one can be removed as that controls the abv.

And that setup is wrong with the vac lines. Will mean your abv is open on boost all the time....

[hugh]

I just crimped the return with the pressure guage in the engine bay, and the car idled around 50psi, but still dropped a little when revving..does that mean that the pump is doing a bit, by pressurising it more than normal because no fuel is returning, but not good enough to produce the correct pressure when revved? ie. it's on it's way out but not there yet..good enough to idle, but not good enough to rev?

KE_Slider: I ran it quickly yesterday with no filter, just the pipe straight through to see if the filter is blocking it, but made no difference.

Goldberg: As far as I'm aware, I am running a stock FPR. I got two others sent to me from a friend, one was all one piece, with the vacuum and fuel line joined to it which I think is a NA 4age one and one had the thread in the top, which my fuel return line has a banjo on it, and that is the one I used...I think it is the 4agze one.

Nikkojoe: I didn't set up the vacuum lines, John (Sprinterman68), who was recommended off the forum did. I can have another look tomorrow at where the vacuum lines go because I may have made a mistake.

[lolwat]

ok buy a new pump BRU

or (sorry if someone has said to already) check for clogged lines(doubtful)

[Nikkojoe]

Yeah I understand. Just get a picture/diagram of where the vac lines go to and then we can see if its correct

[hugh]

So I bought a new pump, and the pressure does the same thing, idles at 30psi, then when you rev it, it bounces around between 20psi and 40psi...I've been told that the vacuum lines may not be connected properly, so I have taken a photo...hop it makes sense...

There is a little pipe out of the top of the ABV which has no vacuum lines running to it at all, and as far as I can see, no VSV

[Nikkojoe]

Incorrect.

Your abv is constantly open so you wont make consistant boost, and the fpr works off the red/brown vsv which you are missing. To make it atleast half decent, there is a vac line port on the intake manifold, move the hose that connects to the throttle body to the intake manifold port and see how it goes. Really though you should need a vsv....

[hugh]

interesting...as I didn't do the vacuum lines, I am unsure or why the red/brown VSV would have been removed...I will have a look at my manifold for the vac line port..
Would I need to vacuum cap the line on the throttle body?

[Nikkojoe]

Yep, block it off.

Best off googling for abv mod, lots of stuff out there.