I have a '13 G37S 6spd. sedan w/ 19,500 miles. So almost as soon as the weather got cold here a loud squeaking/grinding noise would happen every time I started the car cold for only a second or two. It sounded like it was coming from the front of the engine, like a squeaky belt or maybe something mechanical making a quick adjustment. If you start the car warm, there is no noise.

My Infiniti service department supposedly diagnosed it and replaced the auto belt tensioner under warranty. That did not fix the problem. Surprisingly, they even replaced the drive belt under warranty. That also did not work. They had the car all day yesterday and today and still cannot track down the source of the noise.

The service advisor thought it might be the A/C clutch or the throwout bearing for the clutch in the transmission. I would be shocked if it is the throwout bearing for the clutch as the noise only lasts for a second or two.

Any ideas?

Thanks!

 

I cleaned the MAFs and problem is gone... Sometimes I happens but rarely.

 

Have them change out the idler pulleys too. If that doesn't fix it have them change out the alternator pulley, if that doesn't fix it have them change out the AC clutch and pulley assembly. If it's under warranty have them throw parts at it, it's not your money.
It sounds like a bad bearing in one of your drive pulleys though. Could be power steering pulley too.

 

Thanks for the advice guys. They put it up on the lift this morning and said it was very loud near the clutch. They think it is a bearing and maybe some other parts near the clutch. That is the last thing I would think it would be, but surprisingly the clutch is under warranty if it is stock. Nice! I was not expecting to hear that.

I thought about actually getting a lightweight flywheel so it would rev quicker, but after reading the reviews on this site about all the chattering noises and talking to the guys at Stillen and CZP, I decided to keep the stock dual mass flywheel.

 

So they replaced the throwout bearing, slave cylinder, and the starter. They think it was the starter. I will find out tomorrow when I start it cold if that fixed it.

Anyone else have their starter go out this early? My car only has about 19,500 miles.

 

Why would a starter make noise after the car was started? Unless it wasn't retracting right away and still hitting the flywheel, but atleast it's free!

 

It was making a ton of noise as it was starting. The new starter actually fixed the problem. Today was the first day in a long time it started cold without making all the noise.

But now it is almost impossible to shift into 6th gear. So now I get to bring it back to the shop tomorrow.