For about a week and a half now my 2006 350z has been giving me a annoying noise when I let off the gas only at lower rpm once I get to about 2500 rpm the sound goes away. Doesn’t happen when Idling other than at cold start I have videos to go along with it. Duly note this is not effecting how the car drives no check engine no loss of mpg no overheating just a very annoying.