chwomac

My car is a stock (no mods) 08 350Z Roadster.

I have a problem with my Z, when I first start it, it runs very rough to the point of almost dying. It gets a little better once it is warmed up but only slightly. It even runs bad out on the road. It sits a lot and is only driven every now and then on sunny days. But with this problem I drive it even less. It is so bad that I am afraid to drive it and it will hardly pull itself unless I rev it and then it revs too high. Once I get it to rev above a certain rpm then it runs fine. So it seems to be an IDLE problem, but not sure.

I had this problem last year, put injector cleaners with water remover with a full tank of fuel. No change after putting these in then driving it some. So next I removed all the fuel from the tank, cleaned it out. (found nothing) Then I pulled out all the injectors and cleaned them and blew out the fuel rail. I did not find anything of any kind, no dirt, trash or water in anything. (at least nothing visible) But that step worked and it ran fine till this spring.

Both times it was running perfectly one day, then I started it the next day and it had this rough running problem. So it seems to be something that happens when it is setting over night. I wonder if it is something to do with the fuel or something in the fuel? I store it in a garage that is very dry, indoors under a cover in the basement of my house in East Tennessee. I have owned it since Spring 2008, it only has 26k miles, it had 5200 when I bought it. I have maintained it well and do not race or push it at all. I only drive it on sunny days and only put about 500 miles per year for the last couple of years. Before that I drove it more regularly.

Any suggestion or help would be Appreciated!

Frustrated in East Tennessee!

jhc

Chwomac,
Welcome, sorry you're having trouble with your Z.

Is it possible that bc it sits that rodents have nested? I have seen where rodents will chew the insulation off wires, making them ground at times.
GL

travlee

iTrader: (8)

reset the ecu, and do the idle air relearn... hell i would do all the relearns at this point. hard to say what it is without seeing or hearing it

good luck sir

Spike100

Have you been able to pull any codes?

chwomac

First, I have not noticed any rodents or any damage such as wires being chewed. I feel for sure that it is fuel related since the last time I simply blew out the fuel rail and it ran fine.

Last year I read the code and it pinpointed to the fuel system. I do not remember what the code was and I simply have not had the time to connect the reader to the car. I will do so soon and then post it when I have a chance. I am simply trying to determine if there is something I could do to prevent from going through the routine of removing the parts to get to the fuel rail and then getting fuel everywhere and blowing out the system. I am wondering if a fuel filter in line would maybe help, but I do not know of one except for the sock on the fuel pump. I also realize that a fuel filter would limit fuel flow and it would not perform well with one. I am thinking it may be WATER in the fuel because at the area I live Mid-Grade and High Grade fuels do not sell all that well and even though the places I get fuel are relatively new (built in the last couple of years) but condensation and contamination from fuel transfer can get transferred to fuel tank.

I just feel that it is strange that both times the car was driven the day before (running perfectly) then the next day it runs very rough!

Spike100

You will benefit getting the codes.

oldschool350z

iTrader: (1)

The code is what the car is telling you whats wrong. Until that issue is fixed the car is still going to show the symptoms.

chwomac

I finally did get a chance to check the codes they are as Follows: PO300 & PO171.

Last year as I recall the codes were PO171 & PO174. Similar but a bit different. According to the manual it could be many things of which I am not sure. But I still think is related to Fuel. I plan on taking the fuel rail out and blow it out with AIR pressure. I am just not sure as to what exactly it is. I may also first drain it into a glass beaker to see if I get some kind of contaminate before I blow it out.

Thanks, to All replys

TWhetsZ

iTrader: (1)

Hope you get your Z sorted out. Good to see a fellow Tennessean on here.