Hi all! I have a 2005 Infiniti G35 and have been having this issue with it. Feels like it starts off in 2nd gear. I took it and had a mechanic look at the transmission about 6 mos ago when this problem started. He said it was the transmission sensor #1. He replaced it and it's been fine until today. Same problem again.
It also started making a rattling noise when it's idling.
Anyone know what it could be or has anyone else had this issue?
thanks!

 

I hope you've posted this on the G35 forums. Not a lot of VQ35 owners here.

 

Well when is last time you changed trans and diff fluid