A guy I know recently picked up an 05 or 06 g35c (automatic) He said he's been hearing a weird noise when it he first starts the car and it shifts from 1st to 2nd. I had him show show me this noise just now and there is a noticeable, yet hard to describe brief buzzing sound. I had him leave it in 1st manually, and it still does this buzzing sound at around 1,600 when there is no gear change. It does this only after every startup and initial launch, but not after that. Is this normal? Fuel pump, ABS? Or should he have it checked out?

 

Could it be bearings in the drive train?

I know in the 6MT that after start up, the same sound can happen and it takes a few seconds for the bearings to get lubed up before they quiet down.

 

Thanks for the reply dude. The weird thing is that it only does this after he re-starts the car. For example, if he starts it up, launches, the noise kicks in for a split second at around 1,600. If he comes to a complete stop and launches again, it does not happen again. But if he turns the engine off, and restarts it right away, it will happen again the first time he get's to that rpm. If that makes any sense. When I heard it for myself, it sounded like like a motor of some sort buzzing for a split second. Really odd. I'm sure it could potentially be a number of things. I was hoping it might be something normal, which it still might be. But I guess it's safest for him to take it to the dealership to see if they can verify whether it's normal or not.

 

SO THATS the sound when I start up... brief 'choking' sound for a second?