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Problem with fuel pressure

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Fos

15+ Year Contributor
41
0
Nov 17, 2005
Tallinn, Europe
Hy, I checked my fuel pressures today and it turned up to be around 7 psi above normal..

I use stock fuel pump and a stock FPR.

Readings were about as followed: with vac: 40 psi, without the vac line: 55 psi... :confused:

I do have the fuelpump rewired but I switched it to normal feed and still got about the same results. Is my fpr gone bad or could it be something else?
 
Do you have an upgraded pump? If so then this is why.. You need an AFPR to bring the base pressure back down.
 
He said he has stock FP and FPR.

As I recall, stock pressure on a 2g with vac line disconnected is 43psi, so you're 12psi high.

If you plan on modding your car and it's in your budget, you might want to consider an AFPR so that you can dial in the correct fuel pressure. Then you'd be ready for a fuel pump upgrade (190 or 255).

Otherwise, you could try changing the FPR. I'm vaguely recalling something about early 2gs having the FPR built into the fuel rail, but that might be a n/t. If not, it's easy to replace.

Are you sure the FP is stock? Maybe a previous owner upgraded but left the stock FPR.

Only other thing I can think of is blockage in the fuel return line.
 
I'm not sure the FP is stock, but I assumed becouse the previous owner didn't mod the car at all. I got it as stock as can be. Allso I remember i't used to run better when i got it :)
. I'm planning to get AFPR today, it'l take some time to install but no biggi.

My freind allso sugessted that I might be getting bad vacum. Leaks in .. I don't know the correct word... "breaking amplifier" :) or intake manifold.

My boost gauge is showing around -0.8 bar (thats -11.5 psi) of vacum... should be normal i guess.

kenamond: 2G's do not have fulerail imbedded fpr's. Atleast turbo ones dont.

I removed the stock FPR to check... no dirt in it. I'm running rich allso, I forgot to mention before.
 
I installed the AFPR and turned down the pressure to 42 base and 33 with vacum but I'm still running rich according to my narrowband. I get the same second or third green light on the "Rich" scale. (I know i'ts not reliable tuning source.)

I will try to adjust a little according to timing tomorrow (right now it stays on 10 degrees on WOT) but I'm afraid that i'm gonna have to turn the fuel pressure too low to get decant timing advance on WOT.

my T25 is running on max... I get about 16 psi sometimes, but most of the time it will not go over 11.5 psi. I guess it's becouse i'm knocking like hell.

Is the size of the FPR vacum hose relevant? I use pretty big hoses.
Can I run the vac hose straight from intake manifold or do i need this acuator thats between the hose coming from intake manifold and FPR?

Any ideas/suggestions are welcome.
 
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