Z does not accelerate

Vicster

I've had almost the exact same issues. Dealt with it myself for a little while but eventually it threw a CEL so I took it to the dealer. They said it was the K&Ns and that oil from them damaged the MAFs and they would need to be replaced and not under warranty. I decided to just clear the CEL myself, clean the filters and ensure no excess oil, and spray the MAFs with MAF cleaner.

It got better immediately and I didn't have an issue for some time. Eventually though I started to get the feeling of overall decreased performance and recently I've had the codes (not the CEL though) thrown. I've cleaned the MAFs a second time which seems to restore some performance but the reaction is sadly random and not very consistent.

I'm beginning to think that maybe the dealer had one thing correct and that is that the MAFs actually need to be replaced. If this is the case I believe K&N warranties their product under Magnuson Moss and will reimburse you for the replacement of parts not covered under manufacturer warranty "apparently caused" by their filters. Thing is, if replacing the MAFs helps and the cause was the filters/oil I wouldn't want to use them anymore (and for that matter any of the CAIs also utilizing oiled filters, which immediately limits some of my favorites. However Stillen has released a new Gen3 dry using AEM filters.).

The other problem is that some of the issues mentioned relating to the throttle sensor definitely make me wonder if that is the problem. Interestingly, before reading this thread my instincts where telling me that it was primarily throttle response which seems to be the symptom. Hard to say exactly what is the problem so I'm very interested in seeing what your experience turns out like.

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-Chris

'13 Z34 Touring Sport | ARK GRiP CBE | Stillen G3 CAI | AAM HFC | UpRev | 20mm Z1 Spacers | StopTech Drilled/Slotted Rotors | StopTech SS Lines

P's_Z

Coincidently, SES light came on today. And I do have K&N filters also. Its dissapointing to think that the oil messed up the MAF sensors,ive used K&N filters in all my previous cars and never had an issue, so that says a lot about how crappy our MAF sensors are. Ill definitely try and go to the dealer this week, really dissapointed in my Z right now

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Zeta

P's_Z

Just a little update, took my car to the dealer, did routine check up but have mostly been working on another forum members car(carlitos Z) which was first before mine. They have done tons of testing and changes in carlitos car, from reprogramming ECU to changing maf sensors and they have still not solved his issue let alone mine. They even tried to blame the motor oil we are using on our car as part of the issue, as neither of us uses nissan ester oil. We gladly responded: "well youre the ones that think this is the issue and are stomped, if you pay for the oil change, well gladly take your oil" They have yet to confirm if they are going to replace it of course. Last but not least, it is rumored that some people in the states that have had this problem have had it resolved by replacing the throttle bodies, which i read here somewhere. Of course being this an expesive alternative to solving our problem, dealer will gladly keep our cars in the meantime checking on other bull****! So, thats all i have to report for now, ill be picking up my Z tomorrow while they work on carlitos car. That we know of, there are 6 people with this issue in PR, some are even forum members. Again, this has been a very dissapointing experience, between the bogus and misterious issue we have that no one seems to be able (or capable) of solving, to the inneficient product that nissan has cooked up. Dont get me wrong, i love my car, and will most likely keep it if the problem is solved, but im definitely frustrated right now. Thanks to all who have written and have been giving me their input on this, as ive even had to give these pointers to the certified mechanics who are working on our cars. I will most likely be writing a very interesting letter to nissan in the upcoming days....

For now...

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Zeta

juld0zer

hey mate, at least you got a CEL!! i have nothing to go by. Just instinct, determination, constant research and speculation.

what mods do you have? how about carlitos?

carlitos_370z

First of all... Thanks Pedro for open a thread with the problems that our Z's have right now... i know this will work with other members in the future...

Ok I dont have to much to say cause Pedro already talk about that... currently Pedro's Z dont have any mod... they remove all the mods to see if the problem go... but still there... From my Z.... right now the only mod that they have is the HPS Post Maf Tubes... Oem catback and oem drop in filters cause the first time i leave my car under warranty they said that the problem was the K&N drop ins... they told me that i have to recharge them... i said they only have 10k miles and we know those filters you have to recharge them every 50k miles... well short story... i put the oem ones and the car still with the problem... I have some friends in this forum with post maf tubes and k&n drop ins for more than 3 years and never had an issue...soo that is not the problem. Today when Pedro pick up his car.. with nothing to do on his car... The person of customer services said that finally are going to clean my car throttles bodies and make an adjustment on them to see if that works... They are going to do that before proceed to change the throttle bodies... if with just cleaning them and the problem go... they are going to do the same on Pedro's Z.

Anyway we are going to keep this thread updated... and we hope that this people finally fix our cars cause this is my 2nd week with out car ands that is my only car right now....

P's_Z

Hey mate!

I didnt a CEL at first, but dealer was able to pull the code anyways, so maybe you can get that looked into anyways.


As far as mods, only the ones on my sig. However, i took all the parts out from my Z and its bone stock now and still have the issue.

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Zeta

Kabestro

This seems to be something bigger in my opinion, you have guys bone stock and mod cars with the same problem. One question, everyone with this issue has had a reflash done to their ECU? I know I did a reflash.

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Stillen Gen 3 CAI / Fast Intentions HFC and CBE 12" Res. (#730) / Swift Springs / 20mm H&R Spacers / Clutch Helper Spring / UpRev Tune 322whp.

P's_Z

No reflash for me or carlitos

However, it does make sense that there might be some problems with the ECU. How can you have the failure now, turn off the car, and then have it working again like nothing happened? Doesnt make sense that dirty maf sensors and/or throttle bodies would do this! I would expect that if my mafs or throttle bodies are dirty, the issue will happen everytime i turn on the car, just like what i have experienced in other cars. Only thing i can think of is the "start cycle" or whatever its called. If this is the case then maybe it makes sense for this to happen. Ill have to start counting how many times it takes turning on the car and have this issue happen lol

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Zeta