Yesterday after parking the car for a short time, the 7AT felt as if it did not want to upshift. When it did , the shifting was very abrupt, almost like a clunk. Drove the car home very gingerly (short distance) Called road side assistance. Before they arrived, I went to move the car to a better spot on the driveway to make it easier for the flatbed. Car had been parked for maybe 10 minutes.

Naturally, it was shifting perfectly from that point on. Dealer has the car now and can not re-produce the issue and no fault codes show. I suggested the "software" patch but they said, that is for the downshift problem. I left the car overnight so they can try again to re-produce the problem. Don't want to pick it up and have it act up again. Its my wife's car but I was drving at the time of the problem. Tried DS mode and manual shifting but it did the same thing till after the "cool down".

Seems to me to be software related so why no "codes" ???

Any ideas or similar behaviors and what was the fix ?

 

emtrey, there seems to be a rather similar problem posted in the tech thread sometime Oct 08. Here is the link.

https://www.myg37.com/forums/engine-...requested.html

This is unusual. Hope you get the fix & let us know of any progress.

 

Thanks...none of the other trans concerns seem to match up w/ my issues.
My big fear is they are going to give the car back to me untouched. The service writer is already giving me the "no fault code" disclaimer. TRUST ME...I am not a "whiner". I have and currently owned some fairly complex cars and try to provide as much input as possible beacuse I know these problems usually disappear when you take the car in for service.

Someone advised a videtape when the car is in a down mdoe as "evidence". Sounds like a great idea. I still a hoping (wishful thinking?) this was a one time glitch or they can acutally find the problem.

He did tell me they would not do any re=programming w/o a fault code. ..I had my MINI CVT trans re-programmed 3 times in the 3 years I owned that car. If this went away after the car sat for 10 minutes, it would appear to be software related. It worked fine after a "re-boot".

At their request, I left the car for another day. Jury is still out..Will advise.

 

Just some thoughts. Even though the S/W may result in the transmission shifting outside of what you'd expect doesn't mean there will or should be codes if it's still operating within reasonable ranges. Having said that, the adaptive shift S/W could be a play here and decide to use these abnormal shift points.

From all the comments I've read on the transmission (downshift, etc.) it's obvious that the 7AT requires a complex control system and it's not impossible that some logic enhancements may be forthcoming to smooth it out under certain conditions. There's also a failsafe mode that locks the transmission into a single gear if it get's confused (i.e. it gets unexpected data from a sensor) and will reset after the car is shut and restarted, and if this is a one time incident the manual claims this is not a problem.

Unfortunately if they can't reproduce it then there's not much they can fix because the control system is doing what it's supposed to. You say this is your wife's car and you were driving it - perhaps your driving style was significantly different enough from your wife's that the adaptive control system handled it by delaying shifting.

 

My biggest hope is that it was a one time event. However, we do both drive the car as it is our "family vehicle" so it has gone from her driving it to my driving. If it did go into a
"protect mode" in this occasion and does not occur again, fine with me.

It did seem reluctant to shift up and when it did it was very abrupt and clunked badly.
My biggest concerns are it happening while she is drving the car and worst case, does any damage long term to the trans. We plan to keep this car a long time.

PS..we have identical cars.

 

Unfortunately ( or fortunately--not sure) they could not reproduce the problem or find any fault codes. Its now back in our hands and I guess ---WE WAIT ............

 

Exact same thing happened to me.

I own a 2009 G37 with less than 3,000 miles on it. Last week, I was in North Carolina driving around the mountains with my 90 year old parents in the car. We decided to go see a campground and we were just idling along, when the car shut off. I restarted the car, and from then on, the car kept shifting between 1st and 2nd gear with a hard clunk. The car would not go beyond 2nd gear. I was not within range of a cell phone tower. I managed to get the car to a KMart in the middle of nowhere. I called Infiniti roadside assistance, got my parents a ride home, and rode in the tow truck 110 miles to the nearest Infiniti dealer, which was in Greenville, South Carolina.

The dealership called me the next day and said they could not reproduce the problem. They said they thought the electronics had somehow become confused and if I had shut the car off and turned it back on, it would have rebooted the electronics and probably would have returned the car to normal. Which I had not done at the time, because I had my very elderly parents in the car and it was 93 degrees that day.

Anyway, I left it for one more day, and when I arrived to pick it up, they said upon further investigation they had been able to reproduce the problem by inducing an error on what they called the CAM SENSOR. They had then replaced a cam sensor. They didn't sound like they were totally convinced that that had been the problem. They said they had never heard of this happening before.

I drove the car 400 miles back to my home in Jacksonville and did not have a recurrence of the problem.

 

weird problem.

 

Sure sounds like the identical issue. My dealer could not reproduce my issue or find a fault code. Had the car back now for over 400 miles and NO ISSUES, I just don't want this to happen while my wife is driving it--it is her car, I just happened to be driving it that night.

However, if it does recur I will lead them down the path you have provided. Thanks for the help