3500 RPM limit issue
 

Just like everyone elses issue with this that I've searched for, 3500 RPM limit, runs fine, but not past that RPM. No Codes, NO CEL or other warning lights. Turned car off, runs fine. 2009 7AT Touring 64,000 miles.

Almost got smashed into pulling out on the highway when it happened :shakes head:

Can someone post a picture/diagram of where the crankshaft position sensor(s) are? Thanks....

did thurning it off, letting sit for a bi, then starting back up fix it?

mine did this awhile back. i tripped a failsafe in the AT and it goes into limp mode. a shut down and restart fixed it.

Yep.... literally pulled into work, shut it off, waited a few minutes, turned it back on to hook up the OBDII code reader, and it was fine...

Did you ever get your 7AT fluid flushed/changed?

yup AT failsafe most likely. didnt even need the reader to figure that out lol

mine tripped when i forgot what gear i was in and did the dreaded 2nd to 1st shift while coming to very steep uphill stop. it was not happy with me.

whole drive home was awful and i thought i blew my transmission. worst 15 minutes ever. called nissan and they confirmed just a failsafe and told me to go start my car back up.......what do you know perfectly fine lol

noooooooooo. also a no-no on the 7AT

Odd though I didn't do anything out of the ordinary? just pulled onto a highway. I've never owned such a goofy car with so many odd "Hey, its normal" issues lol.

well think of it this way it went into that mode because something was wrong and would have blown your transmission and cost you about $4k. i'll go with pulling over and restarting my car. :tiphat:

Perfect reason why manual > AT

:stirthepot:

dont even get me started.

havent we gone through this and proven the 7AT blows the 6MT away in all aspects. yes.

....AANNYYYWWWaaayyyyyyyy..... hah

I'm wondering if it is the crankshaft position sensor, since it was that catalytic converter on that side that failed, and also was red hot... for 40 bucks I'll just replace the sensor...

could be it. like i said when this happened to me it was just the AT sensor feeling something was wrong and hit limp mode.

You really don't change your trans fluids? Do you track your car at all? I know they say its good for life but I'm leaving any fluid in a car for it's life when it's been abused.

The manual says no, most dealer says no, but other owners on this forum have posted they've had theirs flushed, even a few who said the dealer said it was necessary..

what i gathered from everything i read that changing the fluid in the 7AT is a bad thing. would i like to based on what i know about cars and wear, yes i would. am i going to? probably not. if something goes wrong then maybe i will. but 30k miles and not one issue aside from previously mentioned hiccup with a sensor tripping.

Yeah same here, even my 350z I had it flushed at 65,000 miles... but i'm hesitant, the one dealer basically said to me the transmission would fail/need replaced before the fluid would ever need changed.

same thing i've read many times.

supposedly it's good for over 100k miles.

the way i drive.....maybe 50k.

I wouldn't let a dealership do it, it's a pain to do so I would only let someone I truly trust do it. I did it at only 12K miles but the car was 4 1/2 years old, I figured since the car has a lot more power I didn't want to trust old fluids to keep it safe.

Ummm....NO. The AT fails in two very important aspcets:

1. It can't hold power
2. It is missing the 'fun' factor of driving a manual

:tiphat:

Sorry OP...back to your regularly scheduled program

Only when it works!:rofl2:

I've driven a lot of cars, MT and AT and never changed the transmission fluid in any of them, and they all lasted way over 100K. Just saying.

Me too. But some people do have a legitimate reason. Most don't but they read it on the internet that they need to. Same goes for oil changes at 3750 mile intervals. That's ok if you use your Z as a taxi in hot, humid climates. I'll stick with once a year or 7500 miles intervals. Also, never had an issue on any vehicles I've owned.

I am so confused as to how that would trigger a fail safe. I've driven an AT SS Camaro in sequential mode and have done similar to what you described. Didn't have any issues. :confused:

camro AT is just plain terrible. have one in inventory right now and tested it......useless.

moving on: the 7AT in the Z has many sensors that will trip the fail safe if there is ever a threat of it being harmed. this being said it also can trip up on it's own on accident which is what i'm thinking mine was. also it takes a lot to trip it since i've been down the drag strip many times, shifting hard at almost 8k RPM, and not broke it or failsafed at the track.

I replaced the crankshaft position sensor... and last night it happened again... shut off the car, turned it back on, still wouldn't rev past 3500rpm, even in park or neutral.. I plugged in my Bluetooth obd2 scanner, no codes, and no CEL.... turned off yet again, then it was fine.

BUT... noticed my oil temp gauge, sometimes reads the lowest number on the gauge, even after driving for 10 minutes, then sometimes reads normal... and it does the back and forth when you turn on the car so I know its not the gauge, and I read in other threads apparently if the oil temp reads goofy (or high) it can cause this limp mode without a CEL or code... I checked the oil today, and its not low.

150 Lubricating System :: Engine Mechanical :: Genuine Nissan Parts :: 370Z Parts (Z34) 2009-2013 :: Nissan Parts, NISMO and Nissan Accessories - Courtesyparts.com

so it's the 370Z SENSOR ASSY OIL TEMP 22630D?

any other ideas?

do you have a multimeter handy? or would you be near a radio shack etc to get a cheapie?

there is some resistance checks you can do on the crank and cam sensors.

how is your oil level?

Sounds like a blown relay somewhere... might be worth checking the fuses.

Another thought that comes to mind is the brake switch sensor may be stuck on. That's what keeps you from going WOT while brake is depressed.

AK370Z had the same problem which was cured by replacing the 2 cam sensors and 1 crank sensor.

brake switch(es) fault would result in extremely lethargic behaviour from a standstill and it would take forever to reach redline

I haven't had any issues since my last post in April. I just changed the oil again last week, and it wasn't low. I did talk to another 370z owner, who had the 3500 RPM limit issue and it was actually related to the seat belt tensioner... which, mine sometimes needs pulled on a few times after I get out to get it to retract, and he said his didn't throw a code, but his seatbelt wouldn't retract at all anymore... so I'm wondering if its related? but.. like I said, so far so good.

seatbelt pretensioner? man that would've taken forever to figure out! i do have an aftermarket amp for my woofer so i'm also considering the possibility of something weird on the brake light circuit. when i get my car back i will disconnect the amp and see what happens.

the seatbelt pretensioner is the pyrotechnic device which tensions the seatbelt in a crash. it's a bit different to the normal ratcheting mechanism which locks when you tug it (no electronics involved).

so for you, the crank sensor solved the problem? do you still have the old one? i need to gather some data on these sensors because the test in the FSM doesnt give me conclusive results

It only happened again that same day after I replaced the sensor, and hasn't happened since. Nah I threw it away... but I'll update if it does ever happen again and what steps I take next.

Finally!
 

I've been dealing with this issue for 3 years. Every time the nissan specialist would come out he couldn't re-create the issue. I sent him this link and videos i've taken myself. Luckily every "fix" they made was covered by nissan. Yesterday though he flew up again to see if he can duplicate this issue and finally it happened to him! He hooked up his data recorder to the car and got loads of data to take back to the engineers. If it ends up being a AT problem i'll be pissed because i just replaced my transmission back at 60,000 miles. I'm just glad he got the data that they were looking for in order to find a solution. my350z forum under 370z section, others have suggested MAF sensor, but we'll see and once i do get results i'll post them.:happydance: