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Muzzy
05-26-2003, 04:06 PM
Fuel line comming from fuel filter goes to the top part of the fuel rail right and the bottom goes from the fuel rail back to the tank right??

IF that is correct then diagnois this problem: fuel is being pumped to FPR but no fuel passes the FPR...is that pump weak or is the FPR bad???

i know it pumping and has pressure because the line gets tight and fat

Kreator
05-26-2003, 04:55 PM
I'm not sure what you meant by which line goes where, but here is a pic: http://www.wam.umd.edu/~iminin/images/pic2.jpg

Red line is running from the fuel pump, and the blue one is the return.

as for your problem... it's really hard to break the fpr, as there is really no possible way for it to break on it's own. I would rather check something before there... so pump, injectors, something getting stuck in the way.

oh and to make sure your pump is actually sending fuel to the rail, just take off the hose after the filter and turn the car on (don't start it).

Muzzy
05-26-2003, 05:33 PM
well i have a 91 so would that it be a different configuration??

Kreator
05-26-2003, 05:41 PM
oh...

Your fpr is sitting on one of the ends of the rail... the line coming out of it is the return line.

Muzzy
05-26-2003, 05:59 PM
yea i know where it is...i jus dont know if thats the source of the problem (not starting) i got everything else to work now it my fuel system they mystifies me....i definately know my fuel pump is crankin and sendin fuel...but its not opening my FPR.

so is my FPR bad or is my pump bad?!?!

like i said the fuel is gettin to the FPR...no further

Kreator
05-26-2003, 06:27 PM
well the fpr is a pretty simple mechanism. it consists of a spring that gets compressed when the pressure (fuel pressire in this case) rises high enough, and allows for the opening of the fuel return line. So if u said the fpr just leaks everything back, you could blame it on it (say spring broke) but in your case, it practically impossible for the fpr to be at fault. So in that case, the only thing you can blame it on is not enough pressure to open the fpr. The cause of which might be weak pump, clogged fuel lines, or injectors stuck open (guessing here, cuz not sure if they'll be able to provide that huge of a pressure drop).

Ok, just to make sure. Did you disconnect the hose after the fpr and turn the car on? As in, are u 100% sure there is no flow after the fpr? If there is, then it's not the fuel systems fault.... if not:

Go to yer local store, get a cheap *** fuel pressure gauge (or any other gauge that measures positive "boost"), plug one of the ends closed (this is to measure exactly the fuel pump pressure, as if you just plug it in the system, it might give you a wrong reading if something else is at fault, plus you might not want to cut the hose to place it in between), and put second one into the "pushing" line. If the pressure goes over 43.5psi (and if your pump is ok, it'll prolly go all the way out of the gauge range), then it's not yer pump. More to that, you'll know that the failure is somewhere in your fuel rail. After that.... i'm not sure. You can take fuel rail out with injectors and turn the car on and see if any of them would leak... taking it off on an s14 is a pita, dunnow bout the s13s. As for the rail being clogged, after rail is out, take the injectors out (don't want all that crap to be stuck inside of them), hook one of the ends to an air compressor, and blow through at highest psi.

These 3 can be done in any order possible (if you don't want to spend money, or don't have a compressor at hand), but checking the fuel pump will prolly be yer best bet.

Muzzy
05-26-2003, 07:51 PM
ok my pressure guage is readin 60psi...how and y the hell is it readin that high???

isnt that too high??

Kreator
05-26-2003, 08:19 PM
ok 60psi as in whole fuel system pressure or just the fuel pump pressure?

if it's just the fuel pump, than it's ok. I'm not sure if that's the correct amount, but it's definately greater than 43.5psi - at which the fpr opens up completely... again, it might need to be higher, but it's not at fault here. Go check the other 2 options then.

if it's the whole system pressure, than that again means your fuel pump is alright, and it also means that somewhere after your gauge there is a clog. 60psi in fuel system would eliminate the issue of leaky injectors...

btw, im me, i can respond faster that way ... aim: I Kreator I

Muzzy
05-27-2003, 10:39 AM
is that high for being after the FRP becasue thats wut m gettin and could this be the reason my engine may be flooding???

Muzzy
05-27-2003, 10:54 AM
how and y the hell is this happening?!!?!
saw it with my own eyes!!!
took the fuel rail off and saw all 4 fire (inject)!!!

kalieaire
05-27-2003, 11:35 AM
bad electrical wiring.

you've probably got a short somewhere, go check the entire wiring harness from the injectors to the ecu.

if you can't find anything wrong, maybe your CAS is messed up, or your ecu.

kalieaire
05-27-2003, 11:50 AM
muzzy, stop making so many posts please.

it's hard for others to follow your problem and diagnose it properly when they don't know all of the information.

instead of narrowing down the possibilities, you're just increasing them.

so instead of having to reiterate everything you've told us, please stick to one post.

anyway. here's what it says exactly in the FSM.

"The pressure regulator maintains the fuel pressure at 299.1 kPa(3.05 kg/cm^2, 43.4 psi). Since the injected ful amount depends on injection pulse duration, it is necessary to maintain the pressure at the above value."

so as long as the FPR is doing its job, then there shouldn't be any problems.

have you gone through my previous posts to search for a "power balance" tes, yet? Have you even tried replacing the seals on your injectors? It takes less than 10 minutes and less than 5 bux to replace the seals with new ones.

if you only decide to chose certain suggestions and ignore others, then you won't solve this problem. Unless of course, you want to keep your engine in a dilapidated state. That's your choice.

Muzzy
05-27-2003, 11:51 AM
CAS?

Muzzy
05-27-2003, 11:55 AM
..ok..i have solved all the other problems these are the new ones.

i have replaced the seals...

u guys failed to notice my fuel lines were backward

this is the first time anyone said anything about "power balance"

Muzzy
05-27-2003, 12:12 PM
ok well after searching and finding out what the hell a power balance test is....how do u propose i go about this SEEING AS HOW MY CAR ISNT RUNNING!?!?!!?

irrelevent!!! (for now)

Red
05-27-2003, 01:28 PM
If its not an obvious problem, and your just spending time and $$ on fixing things that dont need done. Bring it to a shop and have them Diag it. Then once they tell you what is wrong you can fix it yourself. Or have them do it.

This site is good for alot of things.. But when it comes to finding out important things like your engine fludding take it to a shop. And get a pro to look at it.