Is 39 and 46 fuel pressure okay?

[onecrazyfoo4u]

Finally got a fuel pressure gauge and t'd it off between the fuel filter and fuel rail. It reads in at 39 psi when idling at about 16 in. Hg of vacuum. And I get about 46 psi when I pull the vacuum line to the fpr. Are these numbers acceptable?

They seem a tiny bit high, the fsm says 36 psi connected and 43 psi disconnected. So I'm about 3 psi too high. Just wondering if it would benefit me to get a nismo fpr to turn it down a little? Just so you know, I've been having rough starts in the morning and at night after work. I have to crank for 10-15 sec. and it misses and acts like it's flooding when I'm trying to start it.

[doridori23]

You ;will not notice a difference by dropping 3psi. Have you done an Archive search on the hard starting problem? (For some reason we have a normal search option and an archive search option and i kicks a lot of people in the face as they don't notice this)

[IanS]

You ;will not notice a difference by dropping 3psi. Have you done an Archive search on the hard starting problem? (For some reason we have a normal search option and an archive search option and i kicks a lot of people in the face as they don't notice this)

yah, you wont find jack unless you search archived. As for dropping fuel pressure, it will help the car run better.

[onecrazyfoo4u]

Sweet, I was wondering why everytime I searched it was only recent stuff, thanks for the info.

So will getting a nismo fpr and lowering it about 3 psi fix my car flooding every morning and having the crappy cold starts? My car also hesitates in boost, I'm wondering if it relates to a fuel problem also?

[CoupedUp]

Does the FSM say 36 PSI with the Vacuum disconnected?

[doridori23]

They seem a tiny bit high, the fsm says 36 psi connected and 43 psi disconnected. So I'm about 3 psi too high. Just wondering if it would benefit me to get a nismo fpr to turn it down a little? Just so you know, I've been having rough starts in the morning and at night after work. I have to crank for 10-15 sec. and it misses and acts like it's flooding when I'm trying to start it.

[CoupedUp]

They seem a tiny bit high, the fsm says 36 psi connected and 43 psi disconnected. So I'm about 3 psi too high. Just wondering if it would benefit me to get a nismo fpr to turn it down a little? Just so you know, I've been having rough starts in the morning and at night after work. I have to crank for 10-15 sec. and it misses and acts like it's flooding when I'm trying to start it.

[rustest86]

mine use to do that it was the lower injector o-rings were leaking flooding the motor. changed o-rings cold start problems went away.

[onecrazyfoo4u]

Yeah, I've heard to check the injectors too. I just ordered a new gasket set for the lower and upper o rings on the injectors. Are the lower o rings the little tiny ones or is that the upper ones?

I tried pulling one out the other day, it wouldn't even budge. I unscrewed the 2 philips screws and used a wrench to try and grip it and pull, couldn't get it out at all....am I missing something here? How do you get the injectors to slide out? Thanks.

[rustest86]

the "right" way, according to the fsm, is to pull the fuel rail and push them out through the bottom. this ensures that you dont damage the injector terminal. also i little trick/ advice, order new pintle caps from nissan, because when you push the injectors out they WILL break. these are said to be useless, but they auctually help hold the lower o-ring in place for being blown out under pressure. also push on the outer edge of the tip, NOT were the holes are you will damage the injector if you do that. they will be very hard to come out. make sure on the new o-rings to grease them or use silicone spray on them.

[Hudsontec]

I tried pulling one out the other day, it wouldn't even budge. I unscrewed the 2 philips screws and used a wrench to try and grip it and pull, couldn't get it out at all....am I missing something here? How do you get the injectors to slide out? Thanks.[/QUOTE]

P.B. Blast will loosen them..

[onecrazyfoo4u]

Cool, thanks for the good advice. What exactly are the pintle caps then? Where are they on the injector/rail? Could I grease the new o rings with somethin like caliper grease, is that okay to use? Thanks again!

[rustest86]

the pintle caps are just peices on plastic that snap on the tips of the injectors. yea any grease will work just dont use excessive amounts, you dont want any clups cloging you injectors. the grease is just to keep the o-rings from tearing or getting cut. just put a light coat on the new o-rings and the injectors pop right back in with very little effort.

[onecrazyfoo4u]

Hey thanks again....I've been looking up info on these pintle caps, can't really find a place to buy them at all. Guess I'll have to go to the dealer for those. I wonder if you could run the injectors without those caps, or if it would cause any harm?

[rustest86]

you can run without the pintle caps but i wouldnt, i say this because ive tryed it. out of 3 without i had 1 injector that keep blowing the lower o-ring out because i didnt have the cap on the injectors. the pintle caps help hold the lower o-ring on the injector in the fuel rail when pressure i aplied by fuel.

[onecrazyfoo4u]

So I pulled my fuel rail out today, all the caps are intacked....but there's no o rings on anything. The only ones, were the large black insulators the went inbetween each injector and the intake manifold. My question its, where do I put these o rings on that I have? I have some really small ones, that I'm guessing go inbetween the pintle cap and metal surrounding, or do they go over the metal surrounding? I also have bigger o rings, but don't see anywhere to put them?

I still can't get a single injector to pop out of the fuel rail....do they need to come out to put the o rings on them? Here's a picture of what all of my injectors looked like, no o rings on a single one:

[efrain240sx]

Yeah how do you take out the injector from the fuel rail. I couldn't take mine out

[onecrazyfoo4u]

No kidding, they're stuck in there like crazy, just don't see how to get them out without destroying the purple plastic casing. Anybody know where these larger upper and smaller lower o rings go? I've got to get it fixed tomorrow. Thanks.

[efrain240sx]

well I know that the o-rings go inside the fuel rail on the injector

[onecrazyfoo4u]

Yeah, both o rings go on the injector. I finally got them out. I used a long flathead screwdriver, and pryed right under the angle connector on the injector....there's a little slot there to barely fit the screw driver.

All of my o rings were perfect, so I didn't even bother with replacing them....they weren't cracked or anything. But I cleaned everything up good, include my fpr, and now the fuel pressure is right at 34 psi. That's wierd, I didn't change anything, just cleaned it good. I'll check it again to make sure it didn't go back up.