Alright, I'll try to keep this as short as possible. I had a turbonetics kit on an '06 350z (~35k miles on car at purchase) that I purchased about 6 months ago. The car ran fine for about 4 months other than a small bit of smoke from a blown turbo seal. Didn't worry too much about it as I had plans to pull the turbo off. Took the car to a Nissan dealership to get looked for some warranty work. The oil pan gasket was leaking a bit so I had them fix it. Upon getting the car back, I took the car out for a spin and noticed it had a bit of an exhaust leak along with not accelerating properly when I got on it. No biggie, figured they just hadn't tightened the exhaust clamp. Got under the car and found the exhaust clamp mangled and rigged up under car. I fixed the clamp and figured the acceleration problem was probably due to a small boost leak. Tightened all the leaks and still had problems. I was planning on putting the car back to stock, so I let it sit about a week and picked up all new replacement stock parts to put on the car. Pulled the turbo and put in stock injectors, stock exhaust and an oem intake. took the car to the dealer and had them flash the new ecu. Car idle's perfect now and will run on the local roads without problem. car is still having acceleration problems. Any time while driving, if you apply decent pressure to the accelerator, it will start to run up and then start bogging down and acting funny until you let off or only apply light pressure to the throttle. its pretty much the exact same thing it was doing with the turbo kit. It only started doing this after i got it back from the dealer that first time. I havent checked the fuel pressure, but i will tomorrow when I'm off. the fuel pump is the walbro 255 (it still has the same setup from when the turbo was in, including regulator). Any ideas as to what this could be? Dealer thinks its the injectors, but I doubt it since I swapped them when i pulled the turbo and getting the same results. No codes being thrown. the car has oem o2 sensors as well. does this sound like a fuel problem being that the problem has remained constant throughout the swap? if so, it wouldnt be because of the walbro 255, would it? (as in too much pressure?) i wonder if nissan damaged something when i had it in the first time. Possibly a crimped fuel line? (will look for that tomorrow.) all ideas and thoughts welcome. Thanks in advance.

edit: probably should have put this in tech section, eh? mod can move if needed!

 

I suggest paragraphs

 

Have you checked the clutch? It sounded like a clutch slip or some sort. I think it would be possible the clutch was burned out due to the FI Z had before. I'm not sure if this is it but worth the inspection. Just my .02

Good luck fixing it

 

I think you are on to something with the fuel pressure. The first thing I would do is double check the fuel pressure. Make sure that the fuel pressure is holding at the appropriate level for the stock ECU flash and injectors. If your fuel pressure is too high or too low, that could create an issue.

 

i did use paragraphs. one big one. just didnt indent the first line. heh, sorry. I get points for punctuation and spelling, though, right?!

as far as the clutch goes, i don't think thats it. the motor isn't revving up while the clutch slips. plus, it isn't a stock clutch. has an aftermarket clutch with lightened flywheel. The motor seems as though it just kinda dogs down as if it's not getting fuel. thank you for the idea, though. much appreciated!

 

alright, thats what i was thinking. any chance you or anyone else might know what the stock pressure should be sitting at? also, how would i go about adjusting it, provided that fuel pressure is the problem?

 

I think it is set at 43.5 psi, but double check.

I have never played with the stock regulator, so I don't know whether it is adjustable. Do some research to find out if there is a problem using a Walbro 255 with a stock fuel system/motor/ecu flash. If so, the problem may be as simple as putting a stock fuel pump back in.

I did a quick google search on Walbro 255 and stock fuel pressure regulator, and here is what I found:

"...in some applications with an OEM stock regulator you may need to upgrade the regulator to avoid issues with too much flow for the OEM components."

http://treperformance.com/i-133067-n...2003-2009.html

 

awesome, man. thank you much for the help. I'll take a look at it tomorrow. If the worst case scenario is popping in a new (oem) fuel pump/ or just upgrading the regulator, I'll be happy. Thanks again!

 

Does your car accelerate in a slow range on first to second from 0 to 3k rpm even you slam the accelerator to the floor? And it wouldn't pass over 3k rpm when it is on 4th gear up, if you have this problem, it may be the your APP sensor giving you the problem. Because that happened to me too, I didn't do anything to it, but after I restarted to car or let it sit for a while then start it then it when back to normal. I don't have code when first started acting stupid, but just happened to me once with a code P1228. I hoped this will help you.