First, I am a brand new member to this forum and know this has been posted before but thought I would share my experience with my "new to me" NV. I just purchased a used 2017 NVP V8 3550 van that had been traded in for a pickup truck with very low mileage. Within 200 miles, my engine started losing power and the RPM's would race up and down. ( I'm not technically inclined! ) Anyway, I called the Nissan dealer in Phoenix, Nissan Avondale ,and they fit me in the next day. They installed the software update for the problem and told me that the issue was that the second fan for the AC was pulling too much power from the engine when it would turn on. Since the second fan does not turn on all the time, the problem was intermitted. Anyway, my problem appears to be resolved and the van is running well now. Thanks to all the information on this site, I was able to steer the dealer to the update and want to let everyone know how helpful your posted were as I encountered this issue. If I had not had this site to go to, I am sure I would have thought I had a bad transmission, instead I knew it was a simple solution. Thanks again everyone for sharing your info. By the way, the Phoenix dealer's service dept was great! Maria