My 05 g35x makes a harsh sound first thing in the morning. The sound is coming from the engine and it sounds like someone is scratching the chalk board with their nails (1 second of pain). It only seems to happen when the cars is not used for a prolong amount of time.

Always hated the kid who scratched the board with his nails!!

 

Sounds like the ABS self check.

 

Yep. It's normal, nothing to worry about.

 

So, I should have been more clear in my description.the sound happens when I'm in motion moving forward.

 

My G35 does it every morning when I'm headed out of my garage. Once I hit about 1500 rpms there's the ABS self check which sounds like a shot of clunking.

You could always take yours to a shop to check it out just to be sure but that's what it sounds like.

 

the ABS self-check is a relatively quiet sounds and does not sound like "someone scratching the chalk board with their nails". also doesn't the ABS self check every time you turn on the car? figo mentioned that the sound is only there when the car is not driven in a while

 

Mine sounds like I ran over a grate. If you have your foot on the pedal when the test happens you can feel it pulsating. Figo, does it happen after every time you start the car and start rolling and then not again? If so that's what you're hearing.

 

The belts are probably slipping.

 

One of us should try and get a decent recording of the ABS prime for when this question comes up.

 

^ I know right! lol