It could be that the FPR does not hold its pressure.. or unless you have a fuel leak somewhere within the lines. I have a feeling it could just be the FPR that doesnt hold the pressure.

I really doubt that your fuel pump is bad... unless by some coincedence it's going bad at this time.
Buy an ebay fpr, yeah I know I'm gonna get "those things suck!!" and " they're pieces of ish!!*" but I bought one and it's been working for me for two moths now(no problems) + I bought it for like 35.00

 

geez,.... what a luck i have huh?
i bought an used fpr by sard from an org member, and it was broken, i bought a new one and that doesn't work either.... what a waste of money sard is...
is there anyway on testing the fpr? they wont accept returns either... i already wasted 200 dollars on 2 fpr's and i want to make sure that this one is broken before i trash it...

 

maybe its not the Fpr in the first place.


my afpr is from ebay. $30 shipped and worked great since the first turn of the key. Make sure to use thread sealant.

 

yeah actually i used thread sealant on all the threading's for the fuel lines and made sure all hoses were tight.

is it possible to have an air pocket in the lines? and if so, how would i get rid of that?

 

I do not think its the FPR because you are getting fuel initially, I'd doubt you would have this symptom with 2 different FPR's Any new codes since changing the CPS?

 

well i havent checked for codes but i doubt there are codes for fuel....

 

Do any of you guys know how much psi our fuel pump is supposed to make?

 

I dont think that the 51 psi can be obtained with just the afpr.

csb got a walbro and was able to get the 51 psi.

 

In retrospect, the 51 PSI thing wasn't necessary by any stretch of the imagination. Kinda silly actually...

 

are you guys telling me our stock fuel pump will not be able to make 51psi with an adjustable FPR?
if not, then a walboro fuel pump is needed?
what can explain for my fuel pressure to drop when car is on idle? it keeps dropping as low as 15psi.... will this be a fuel pump problem? or my brand new SARD FPR came damaged?
need help guys... thanx.

 

The stock fuel pump does the trick for most people but the funny thing is that me and my friend bother have the SARD FPR and we both had the same issue you are having. We just upgraded out fuel pumps to Walbro 255 HLP and all the issues went away. I had a brand new SARD FPR and he had a used one. I say just upgrade the pump and call it a day.

Mike

 

I run the stocker with a SARD fpr and I get too much pressure. 75psi at start-up. I need to replace the FPR.

 

just to note. dont forget to make sure the gasket in any afpr is seated properly and apply (if needed) thread sealant to all threads.

 

alrighty guys. thanx.
i guess my fuel pump is too weak.
i will be ordering the Walbro today..... i hope this will kill the last problem with my car.

 

you car would and should still start and drive fine with a working stock fuel pump.

 

hey Deezy,
is there a way for the stock fuel pump to get weak?
why would you think my pressure just drops like that?
when priming the system, it does not want to make more than 30psi, and when i turn on the car, it just keeps droping until the motor dies within seconds.
then when i prime the system again, it jumps back to 30.... im very puzzled...

 

I havent seen a case of fuel pumps getting weak, they either work or dont. If you had zero fuel/fuel pump issues before the swap, it seems like you could rule it out.

I believe you can test the fuel pump with a multimeter (not 100% sure), check the fsm or haynes.

you sure you dont have any vacuum leaks either?

all fuel lines routed properly to the afpr and to the tank

 

I here what everyone is saying but I guess every ones situation is different. It just turned out that me and my friend had the same exact problem and the solution to the problem was to upgrade the fuel pump. I researched the 3.5 swap for 5 months before I did mine and had all the parts including the motor 2 months before I even did it. So I know that in no thread did they say it was required to upgrade the fuel pump. But since that was the only thing my mechanic could suggest to fix the problem....I went ahead and purchased. But now that I think about it, we purchased our FPR from the same person except mines was new and his was used....Hmmmm. So maybe this guy had faulty FPR.

 

hey Mdeezy, im pretty sure i dont have any leaks on any of my fuel hoses.
which vacuum leaks will cause me to lose fuel pressure?
i have a quetions....how does the return line hose look like? maybe i have one end of the fpr plugged to the wrong return line?
is it recommended for the fpr to be placed near the fuel rail? would it make a difference?

 

FPR doesnt make a difference as long as its properly hooked up.

The return hose-> look at your fuel filter's feed line coming from the gas tank, the hose next to it that also goes to the gas tank, thats the return line.

On both FPR that I've had, the inlet was on the side, the outlet at the bottom.

I ran my 3.5 for a few months with no problems at all with the stock fuel pump, I just upgraded to a Walbro 190 because my friend got rid of it. I didnt really have a need for it at all. Your problem IMO based on my experience, its the FPR, not pump. When FPR go bad they either dont hold pressure (your case) or the seize (my case with my original ebay greddy knock off FPR, siezed at 75psi like it happened to Stabone). Contact Justin from ImportCarPartsPr (he's on the GD forum), ask him for a Fuelab AFPR. They're expensive ($139 shipped) but well worth it.

 

Hmm, I had DE-K injectors (larger than 3.5), stock everything and it seemed to run great.

 

man.... i buy a brand new SARD FPR and it comes broken and they wont even exchange it for another one "Due to racing nature of the product"....
what a bunch of crap! im out of luck. buy a used one broken, buy a brand new one deffective.... i guess the third one might come broken again...

 

The new one turned out to be broken too? I thought it was working when we got it started last night.

 

i gotta check it out again.... seems like it wont hold more pressure than 40psi.

 

^ What pump do you have again? I thought the stock pump maxes out at 43ish.

 

i have the stock pump, but im positive the pump could do more than fifty.
but either way, the Adjustable FPR should be able to make more pressure

 

The pump makes WAY more than 50. I've accidentally had mine up to around 70psi before...this is at idle of course.

Get yourself a NISMO FPR and get done with it!!!

 

hey guys.... i have a question....
with both front wheels off, and i turned on my car... on idle, only the driver side was spinning and my pass. side was not spinning at all....
is that normal? or did i put the tranny back together wrong?

 

Unless you have VLSD, that is what open differentials do.

 

so you are telling me that it is normal right?

 

yes, thats normal

 

ok thanx for the help guys.... sorry for so many questions.
i dont have much time to work on my car these days so im working on it little by little.
what is the best way to seal up the valve cover......
it seems like im leaking some oil on both of them, even though i put a good amount of RTV sealant on the valve cover towards the front of the engine like its supposed to.... any hints?

 

A new gasket perhaps?

 

huhmm....not sure eric....
i was told to put some sealant around a certain area on the valve cover....
will try that tomorrow, hopefully it'll workout!

 

yeah, there is a spot with the channels for rtv by the front cam bearing cap iirc, permetex grey ftw

 

one question guys...
where is the best place to mount the gauge and why does the fuel pressure need to be set to 51 psi? i dont think this was explained in any write up..
just out of curiosity to understand it better... thanx.

 

It doesn't.

 

The base/stock fuel pressure that is required by the VQ35DE is 51 PSI ... a couple over the VQ30DE which requires 44-45-46 PSI... something like that.

EDIT: Forgot to say that the VQ30DE varied its fuel pressure and increased it as RPMs increased. The VQ35DE keeps 51 PSI constant throughtout all RPMs.

 

Engines don't "require" a certain fuel pressure. Two completely different things. There's nothing wrong with running the stock 3.0 FPR on the 3.5 fuel rail and running it with vacuum to it. There are advantages, however, to running a "returnless" setup. Me and a couple others were proponents of the whole 51 PSI thing but in retrospect it's completely false. Quite silly, actually. If one is using the 3.5 ECU and such that is programmed with 51 PSI in mind then that's another thing. But with 3.0 ECU stock fuel pressure is fine.


Also the 3.0 FPR changes fuel pressure according to manifold vacuum, not RPM.

 

FWIW, the stock A32 pump maxed out at 46psi on my car under WOT (with DEK injectors).