fuel issues

[eastcoastchaos]

problem number 6056983726.car drove awesome this morning on the way to work, but when i left it was idleing a little funny and bogging down a bit. it got me a few blocks before it started cutting out really bad.i happend to have my fuel pressure gauge on me at the time so i pulled over to check it out. w/ the key in the on position but not started it hit like 22 psi then pretty quickly dropped to 18ish, i fired it up and it was at 39.while it read 39 it was idleing smooth so i drove a little further, about another 4 blocks. then it started to die unless i was hitting the throttle repededly. i opened the hood and gas was spraying out of the pressure gauge hose. thats as much testing as i've done.i pulled out the fuel pump to look at the wires in there and thay all look ok.

anyone have any ideas.

[NISTECH]

My first suggestion would be to fix your fuel gauge so it wont spray fuel everywhere. Then retry your test to see if it is actually loosing fuel pressure. Looking a t fuel pump wiring wont tell you if the pump is bad. You need the gauge to do that.

[eastcoastchaos]

i'm honored10,000th post. congratulationsi know, the gauge did work for the first two tests. and after the second short drive with it still attached it split the hose.

[eastcoastchaos]

my aim is eastcoastchaos22 if you have a min

[NISTECH]

I hadent even noticed I reached that point..lol I dont really track my post count, actually I could do without it. It just shows how much time I spend on here and really shouldnt..lol

I dont have any messengers anymore. Still have yahoo but havent signed in on that in probably months.

[eastcoastchaos]

i got a whole new fuel pump assembly and put that in (it was cheap and i didn't really think it would work). it ran great for a couple min. i went to drive it the next day and same problem, no fuel pressure and it bogs-stall. i've got wire and what not, should i just re-wire the whole thing?

by the way, new fuel pump, fuel filter has only about 1000 miles on it and all the hoses look good.

[Chezedik]

39 PSI at idle at the regulator is normal. Figure this at 0 " Hg, your regulator will run at 43 PSI. So, since it references manifold pressure at 1:1, if you have 8" Hg of vaccum, that (if it could be thought of as pressure, would be -4 PSI), would make a regulated pressure of 39 PSI. When you say it is cutting out, what RPM does it do it at? Are you sure it is a fuel problem? FOR GOD'S SAKE, FIX THAT LEAK BEFORE SOMEONE'S FIXING YOU WITH SKIN GRAFTS! That said, we need more info, from a guy who is killing himself on a fuel issue, I have taken quite an education lately on diagnosis of fuel problems, and am happy to help, but we NEED MORE INFO.

[NISTECH]

Are you loosig fuel pressure on your gauge while you are driving?

[eastcoastchaos]

it's very fikle. i got it to be a little bit consistantly bad today and got the gauge back working. this is what happened when tested in the on position:test 143 psi for a few seconds then quickly drops to 0test 2at 43 i then pinched the return line, pressure jumped to 55ish then down to 43 and held.test 3 43 psi then i pinched feed line and it did notheing, pressure dropped in a few seconds.test 443 psi w/ both lines pinched it jumps to 55ish then back to 43 and holds.

does that mean the fpr is crappin out or did i maybe screw up the lines when i replaced the fuel pump?thats all i've got for now.thanks for your help

[NISTECH]

FPR is poo poo replace it.

[wilfonzo]

allright, i've got all the parts lined up to fix it but i'd just like to be a little more confident in what went wrong.i pulled the fuel rail in hopes of just putting on my buddys extra fpr. the #1 injector was cracked and leaked a little gas on the manifold.is that just a weird coincidence or could that have anything to do with it. i'm pretty sure the fpr is bad too but what the hell happened to the injector. i should have it working tomorrow. i'm getting a whole new fuel rail w/ injectors and fpr.thanks again

[eastcoastchaos]

oops that last post was from me. i was at wilfonzo's house.

[NISTECH]

Your injector wasnet leaking while it was installed during your test. this you could tell when you pinched off both fuel lines trapping the fuel pressure in the rail.

[Chezedik]

Did you hear that Nistech, I finally diagnosed a fuel problem! If only it were my own...

[Chezedik]

Just re-read my post, and I didn't get that one either, sorry.

[eastcoastchaos]

f ****. i put a new fpr and injector on, i made sure not to tear the injector o ring.i put it in the on position. 40psi, then when the fuel pump shut off i hear a little click and the pressure drops. if i pinch feed and return line pressure holds. i tried again w/ all the injector plugs pulled and the pressure held. so i tried again w/ them re-connected and pressure held w/ nothing pinched. so i fire it up it holds idle and revs perfect, reverse was fine then i put it in first and the idle drops off and stalls. i restarted and the tach spun all the way up then back down and started, then sputtered and stalled.wtf is wrong w/ my ****.sorry for so much rediculous inconsistancy. if it would stay the same i think i could fix it but it continues to work for a min then die. then work again the next day and crap out that night.

[NISTECH]

Trying to help you with this is gonna be hard since it is an intermitten problem. Hell I have a tough enough time with intermitten problems at the shop. The best way to find these type of problems is to have an experianced eye/hands on the car when it fails as there are other things that can be key in determining what the failure may be. Things you may find normal that I would not. At this point you could conduct the leak down test all day long and not find the problem. when it dies can you see the fuel pressure gauge as it is dieing? If so what is it doing as the car dies.

[eastcoastchaos]

seems like there is a little bit of a delay but the car starts to drop idle and run rough then it dies and then the fuel quickly drops off. idk if the gauge maybe sticks or what.

[NISTECH]

When the ECM sees a loss of tac signal it will shut off the pump. Now the problem here is the pressure should remain after it dies. But it doesnt. So you are loosing fuel pressure. It could be the car is flooding out at idle due to a stuck open injector. This would also coincide with the fuel pressure loss. When you restart it does it shoot a huge black cloud out the tail pipe? If so that to indicates excessive fuel dump in the cyl.

[eastcoastchaos]

**** again, fuel pressure is holding rock solid now and so is the idle till it drops just a little bit then it quickly dies. this is bull crap

[wilfonzo]

ha, stuck injector i called it, fix your car, nancy

[NISTECH]

Its a car dude, dont let it get the best of you. Its just a machine.

[eastcoastchaos]

no it's not a stuck injector fuctard(in regards to wilfonzo). and no black smoke. it finally showed a little consistancy today. it idles perfect for about 5 min. then starts to run rough and die. fuel pressure is holding now w/ the new fpr and injector.so it runs good till it warms up, at least all 3 times i tried that today. i checked the fsm for that and have gotten up to wiring issues. i need to mess w/ that a little.how much does nissan normally charge for something like this, and can i trust them w/ my baby.thanks nistech for all your help

[NISTECH]

first try disconnecting your O2 sensor and see if there is an improvement. If not then try your coolant temp sensor.

[wilfonzo]

o well sometimes im right, sometimes im wrong

[eastcoastchaos]

coolant tem sensor it is. good call and thanks again nistech. i had to rewire a new plug a while back and the tape i put on it came off and the 2 wires were touching. it works for now so will see what happens