Twice i drove up north, where outside temperature were about 20-30 deg. F and i found my 09 g37x dropping rpms by violently jerking. After i released the gas, i continued driving and my rpm's would limit to 2,000rpms with some jerking if i tried to give more gas. I've read some other issues, could it be the MAFS? Any other remedies/causes? Thanks

 

Could have been your traction control initiating. Were the roads icy/snowy?

Thats what I feel when I take a 50mph corner, and forget to turn off traction control!!

 

Sounds like traction control kicking in. Is the slip light flashing?

 

Do you have intakes? Is it humid/raining? I have this issue with my injen intakes, even with hydro shields the MAFS will detect moisture and cut the rpms at 2k-3k just reset the ecu and report back

 

I had the same issue today, and it's the 2nd time this month. I actually snapped a video while i was getting off of the highway. The car is jerking, as Dreamon states, violently. It is NOT traction control kicking in. I live in Wisconsin, traction control kicks in regularly, so I know what that feels like.
When i pulled over, i put it in Neutral and gave it gas, and it was stuttering. I shut the car off, waited literally 5 seconds, turned it back on a continued driving without any issue. My nearest infiniti dealer is over an hour away and the nearest nissan dealer, 35 minutes away, only has a nissan tech available twice a week. I'll get to him when our schedules match to find out what is going on.

 

Car is stock. Issue is not traction control. After a violent jerk, car wouldn't let me drive past 2,000rpm even when trying to manual shift. QcM21 please keep me updated on any diagnostic, thank you.

 

Sounds like water in the Gas tank!

 

That used to happen to me but then I realized why...I was using a carwash that would move around the car so when it came to rinse the car from the front, the water would go right through the grille. When punching it down the road, it would violently jerk back and forth until I let off the gas. Use a different wash and never happened again!

 

I was thinking water in the gas tank as well. I put Iso-Heet in my tank every other fill up during the winter, but water could still be in there I suppose.
I have an appointment on Feb 6 to have the car checked out, can't get in any sooner.

 

GL! with everything.

 

Any update?

It's been a year now, and the violent jerking just happend again this morning. I do have stillen gen 3 intake on the car. I would say this generally happens in the cold, although, it did happen to me twice in the summer.

 

I had the TCM/ECM updated, saw something in the TSB forum, and haven't had the problem since. However, i had the car fro 18 months prior to my couple instances without any issues as well.....

 

I had this same problem with my 09 G37 sedan when it was only about a year old.
I happened twice after stopping at a stop sign, when i hit the gas it had a really bad skip
with violent jerking. Took it in to infiniti and the updated the software, may have been the tranny software. I haven't had the problem since. Hope this helps.