rundown of the car:
ati procharger
walbro 255 with return line
fpr
380cc injectors
ts reflash

what happened:
i just bought the car but kit has been on for 5k
last week im driving at low hwy speeds and i feel the throttle loosen up and start stuttering like im running out of gas... ive read about the numerous gauge problems so im thinking i might have ran out of gas... the fuel pressure gauge is showing 20psi as i glide into the gas station... the car takes 10 gallons so i know it had gas... i try to start the car and it wont even idle... fp gauge reads 0psi.. i try this about 4 more times over the course of 3 hours until i break down and have it towed... i check all the plumbing visible to me and find no pressurized leaks... at first i thought it was a leak but come to realize the puddle of gas i see is from over flow of the tank... from the time i get it home till now it will idle fine at 20psi but i wont dare drive it till it reads 40psi like it normally does... z1 is in carrolton but thats a very expensive tow bill... therefore im trying to do what i can first... mike has suggested changing the o ring and then the fuel pump... anyone have a similar problem? any advice is appreciated... thanks rob

 

Rob,
After talking to you on the phone last week I realized that maybe there is air trapped in the fuel line. Have you tried reving the motor to try and bleed the air out? This once happened in an older mustang of mine after running out of gas. Try changing the O-ring as we talked about, most likely that is your leak since it has only occured while the tank is really full. let me know what happens.
MIKE

 

I have a fuel pressure problem, but nothing like yours. Mine is just causing slow starts. I started a separate thread on this. I am changing the o-ring as well and will let you know what happens.

 

Sounds like a dead fuel pump.

 

but would it still idle at 20 psi if the fuel pump was in fact dead... till today it hadnt been showing a cel... i tried to do the technosquare reset about fivr times but my timing must be off because i cant get the cel to blink

 

Keep trying with the ecu reset procedure. Count out loud to yourself or use a stop watch, it will clear. Will the car idle currently? If so what happens when you start to rev the motor? Have you tried pulling the vac line off of the regulator to see what happens to fuel pressure then? The pressure should go up some.
When the pump was bad initially, I found that the gauge wouldn't show any pressure and the pump was abnormally loud. I still think there is air trapped in the line causing fause readings at the gauge. I also still think that the cel you had mentioned to me on the phone is due to the same reason that the gas drips from tank when it is full; the o-ring. How the o-ring has gone bad is a mystery to me if it is indeed bad. Lets hope that's all it is since it is super easy to get to and change. Keep in touch, try my email if you want michael@rowe.nextelbroadband.net or call if need be.
Sorry that things haven't been so smooth,
MIKE

 

the car idles at 20 psi but when reved the fp gauge just dips down a bit... the fuel pump is running loud it seems... we took out the assembly last night and saw that the feed line on the bottom of the pump has broken tabs around it.. maybe this is causing the fuel to loose pressure where that small oring is... or maybe the pump or fpr is bad... tonight im gonna siphon out some gas to give me some room to work then ill see if there is a pressurized leak at that feed line coming off the fuel pump... i guess ill figure out what it is it just might take alot of time or maybe we will stumble on the problem... would the ecu be in a safe mode or anything causing me to only function at 20 psi

 

The ecu never sees the fuel pressure, but will notice if the tank hasn't sealed properly such as leaving the gas cap open or the large o-ring leaking that seats the plastic pump housing to the tank. The pump is bad. Here's the website where the pump was purchased from: http://www.gruppe-s.com/350z/zeng.htm They have all my info in their computer and the pump should have the warranty remaining since it is only about nine months old. I have done some research on these pumps and lots of people are on their second and third pumps unfortunately.
MIKE