tprelude-370z

First off thank you for taking a look at this and offering your expertise. Quick overview of what happened. No prior issues. Gassed car up drove 1 mile home. Next morning drive a mile to the store. On my way home from the store car starts sputtering/missfiring and will not exceed 2500 rpm (limp mode). As I was leaving the store I kind of got stuck in the snow spinning my wheels for a little bit before breaking free. The problem started immediately after that. Brief description of attempted fixes below

MODS - stillen short ram, full header back custom exhaust, uprev tuned.
2009 touring sport - 18000 miles

Initially I thought bad gas which is still a possibility. Weird coincidence is I always fill up the tank only half way because I don't drive much and a tank lasts me for a while. This was the first time in a long time I filled it all the way.

The other variable was the snow incident. Maybe something got wet that should not have (Bad 02 sensor I don't believe causes limp mode but not 100% sure). I have been in snow deeper than that many times without issue. It's a reach but thought I would let you know. It has also been a very cold winter here in chicago with many neg temperatures. Never had any problem though, car ran like a champ.

Did a lot of research of the issue and the codes and here is what I came up with/checked. Did multiple ecu resets (disconnect neg battery at least 10 min (I did it overnight).

Gas cap. no issues tried multiple clicks even.

Low oil pressure. Please do not judge or give me crap about this as I don't drive very much and the car had been sitting most of the summer. I checked the oil and it was bone dry. I know it is inexcusable but there is nothing I can do about it now except move fwd. We have all made mistakes at some point with our toys. There was enough to keep the engine lubricated and this is clearly a sensor/electrical issue. Go to dealer get oil changed, explain the situation and they reset the code then sent me on my way with the car "fixed". Drove about 15 ft and the cel starts flashing again and symptoms repeat. They didn't want to deal with it when I brought it right back because of the aftermarket mods and the fact it has been tuned. He said they would, but at least wanted the computer to a stock map.

Next try was MAF. Common fix for this issue just cleaning them. They looked brand new but I did it anyway (also cleaned all connecters). I cleaned the dirty air filters thorough like new as they were pretty dirty. Pulled the piping checked for debris as well as the throttle body. Everything looked great, like new. Checked all vacuum lines, very diligent to avoid anything air leaks. Reset the computer again, no change. Idles extremely poorly, loud, etc... limp mode. Tried reset multiple efforts to no avail.

More searching found multiple other possibilities as far what it could be and found these potential fixes. Exhaust leak, some rare sprocket issues, and some other random fixes from a fuze to even a brake light out. These were actual posts. My next thought is replacing the MAFs. That seems like the most logical fix but who knows. I also thought about taking it to an uprev tuner to see if they can fix the issue with their software/tune. I would like to exhaust what I can check on my own before taking it to a tuner shop (there are local shops with good reputations). Since there are so many variables and so many things it could be, I would rather try on my own before paying possibly a lot of money to troubleshoot.

CODES below:

p0300 (end all be all when comp doesn't know whats wrong)

ignition
cylinder missfire (more than likely because of the ratios in limp mode)
fuel system
large vacuum leak
MAF fault
O2 sensor

0011 (not likely the issues, thrown more than likely because of the other symptoms)

intake valve timing control circuit failure
IVT control selenoid
cam/ crank sensor
dirt buildup at control valve

1421

cold start emission reduction strategy monitoring.
Lack of air intake volume engine mechanical fault
plugged air filter
fuel injection system fault.

What do you think, fuel stabilizer? Octane boost? a hail mary to improve the gas a tad? Draining the tank would not be an option for me, I would have to take it somewhere.

Any thoughts would be very helpful. Thanks guys.

samsniss350z

your p0300 is a random misfire, and your p0011 is intake valve timing control. Could it possibly be a knock sensor as when these fail there is a slight misfire and a loss of power but then again if you connected it up to a reader it would show P0327. Is there any way you got your filters drenched/dirty as these would struggle to breathe when wet and cause a loss of power.

sandthepilot

Hey guys, I've had the same issue for 2 years and my car is bone stock 2009. I've taken it to the dealer several times and finally last year i've been working with a nissan specialist who drove down to inspect the car and hooked up a data recorder since no codes would pop up while mine was occurring at 3500rpm. We replaced some sensors and it still happened. I have also shown him another thread of this issue that we are not alone with this problem. Nissan itself is denying that there is a problem, but the specialist agreed with me that its ********. The engineers want to try doing something with the valves I will let you know what that is and hopefully the issue will be resolved. I told them im not paying ****! My car is out of warranty and they agreed not to have me pay since i've been complaining about this issue for 2 years. The engineers themselves can't pinpoint the actual problem, but we have been trying one thing after another.

Firebase99

My gut says its the MAF sensor.

sandthepilot

Alright so good news! Nissan Specialist flew up here again to drive the car around to re-create the issue, which before it didnt occur for him. Anyway, it finally happened! And he got loads of data to be analyzed by the nissan engineers back at HQ. I'll let you all know what the results are and the solution. This will solve many of the Z owners problems who've had the same issue as me.

P.S. never buying a nissan again

JPAus350z

Bump! Need answers haha