PeterUbers

iTrader: (1)

So I have 30k miles of MOST trouble free driving, about 5k miles ago, was coming to a stop and the car started bucking violently and I tried to accelerate and it felt like it kept hitting the rev limiter, although at only about 2000 rpms...

Took it in, and guess what.. nothing wrong... they told me it was a fluke thing, don't worry, hopefully it doesn't come back.


A week ago, was in cruise control at 40mph, no foot on brake or accel pedal, and as the car tried to down shift going up a medium incline while in cruise control, the tranny did some weird shifting and all of a sudden, it felt like it was hitting the rev limiter again and bucking/jerking violently...

Pulled over, shut the car off, then turned it on immediatley again, problem gone. Just like the first time -- all I have to do is turn it off, and turn it back on again -- no waiting in between.

Gunna take it in.. I'm going to see if the new tranny TSB helps this out.

RaulGCustom

iTrader: (50)

thats sucks, take it to the dealer

6mtg37s

iTrader: (1)

Yea get it looked at

PeterUbers

iTrader: (1)

Gunna take it in this saturday...

malice9999

Has it been raining? My first car (toyota) had the same symptoms, but would only do it in the rain. Turns out the windshield was leaking into the ECU and causing it to short out.

allagaroo

Sounds like its going into limp mode. Happened to me in heavy rain when the car was app.2-3 weeks old. Car shuddered sitting at a light and when light changed and I tried to accelerate I felt like I hit a wall. When I got to my destination (carefully) I shut car off and when I left car was fine.Diagnostics showed nothing and it never happened again. Have car for 11 months. I'd still check it out.

Chris11LE

I just read a similar story on g35 driver, took a while for him to recreate it as well. Not sure what ever came of it though.

Linky: New G37x With A Big Problem : G35 and G37 General Discussions

PeterUbers

iTrader: (1)

No rain, no inclement weather... happened in colder weather, however -- sub 30's F.

I suspect the dealer will not be able to replicate this -- but I should mention this..

each time this occurred, the car was DOWN shifting .. and i could feel the harsher down shift and then the next thing i felt was the rev limiter like sensation "hitting a wall" until I coasted to a stop.

There's nothing worse than a concerning problem that you cannot replicate.

Gobbler Man

there may be something to the fuse box shorting out. i had that problem on a different car. the worst problem was that the car would cut off, even if i was driving on the freeway. i would fight to pull over. put it in park and start it back up. never put out a code. finally the fuse box finished itself off and they found the problem in seconds.

PeterUbers

iTrader: (1)

The car's electrical system is always intact during these episodes, the engine does not make any strange noises, there is no strange smells, braking is normal, no dimming of lights, no check engine lights, no anything.. just the car feeling like it's hitting the rev limiter -- worse with more acceleration.

It seems that it must be something that is easily reset when i shut the car off then turn it on again -- therefore software issues may be the culprit.

I'm hoping the new transmission TSB, if it applies to my car, will help the issue as i feel that it's linked to the downshifting of the transmission, almost like it missed the downshift and goes into limp mode...

aliang01

I have the same problem now. I sent it to Infiniti of Tysons hoping for a reflash but instead they told me that my car doesn't qualify. Instead they RESET my tranny. I was hoping for a great drive afterwards since it was reset to factory. Boy was I wrong. Now when shifting between gears or even coming to a stop, it shakes violently and when I step on the throttle it feels like its not catching any gears for a few seconds and then jerks forward. Very dangerous. I hope its a software issue and not my transmission gone bad. Either way I hope warranty is as good as they promised!

Doggy

iTrader: (12)

Raise hell until they fix it!

PeterUbers

iTrader: (1)

You NEED the tranny reprogram.

Almatti

Check the Thread about the Transmissions and print out the TSB called ITB10-075. Bring that in to your Dealer and see if your VIN qualifies. After applying the Reflash of the ECU, make sure they RESET the ECM also. Many members have reported a difference in the behavior - mostly positive. Good Luck. PS, you are using Premium gas, ?? Car will behave differently if you don't.

fasteddie

I did a post back in Dec 2010 regarding the same problem. After the 4th episode and being told that there were no DTCs, I dropped the car off at the dealer and asked them not to call me until the car was fixed. Because I mentioned the "hard downshift", 2 weeks later they looked into the trans fluid and found "radiator coolant." Subsequently, they replaced the transmission and the radiator. I got the car back the 2nd week of Jan 2011, have put about 400 miles on the car and so far have not had another episode. I am keeping my fingers crossed. However, the 2009 G37 loaner with 20,000 miles on it that they provided did the same thing after driving it for one week.