2009 G37X Coupe with 7AT

Been noticing some peculiar behavior during normal acceleration. Usually happens when I get around 40mph and from my guess shifting between 3 and 4 or 4 and 5.

While accelerating my RPM's will suddenly surge up from 2000 to around 4000 and then drop rapidly down. Its kind of like when you miss a gear when shifting a manual. No consistency to it. May happen one day but not another. Doesn't matter if the car is warm or cold. Happens more while driving straight but has happened a few times driving around a curve which in turn makes the car feel quite unstable for a few seconds.

It did do it once pulling out into traffic and the car shot forward quite rapidly. My wife thought I "punched it" but I had not.

David

 

Do you have taken the car to the dealer to get the transmission reprogram?There is a Bulleting service for the automatic transmission

 

Thanks,
I took my car to the dealer not long after I got it for some warranty work and was told that they also "performed some updates". I just looked back at my service receipt and there is no mention of it. I'm familiar with the service bulletin and will call them on Monday to see if they can take care of it for me.

Thanks for the reply,

David