Stock (aside from an Exedy twin-plate) Evolution IX, 76K on it, timing belt service done 4k ago at a Mitsu dealer.

It's odd. Start the car, let it run, and it doesn't make the sound (a whra-whra-whra kind of whirring) until you start moving forward. It does this for about 15-20 seconds, then goes away.

Thoughts? Is this something I should be concerned about? It just started doing this about 500 miles ago. I'm not leaking anything that I can see.

 

Update... it does make the whirring if you're sitting still. Got out and tried to locate it, but it clammed up before I could, definitely in the engine bay!

 

Mine has a similiar noise to what I think you mean, pretty sure its the gears in my trans turning when in neutral since the clutch is out the input shaft is turning its turning some of the gears and it makes a weird noise especially with the cams with the lope so the noise also has a lope to it too. Try and put your ear to the trans, when I had my trans fill plug out while running (just for couple seconds) I could hear it best from inside there, I'm not worried it right now but it does bug me, I am also running a little bit thicker oil so that might have something to do with it.

 

Hmmm. Well, this sound is heard both when I'm driving, and while it's still. No change in the pitch / frequency when I'm moving, either.