[cv8]

Originally Posted by elp_jc

Hey OP, could you make a quick sound clip??? The way you described it sounds like piston slap or a main bearing about to go out. Since you said it started making the noise recently, sounds more like the latter to me. If noise is that awful, I'd take it in man. Plus there's a history of main bearing problems with early M3 engines, although no failures.... yet! Good luck, and please keep us posted.

I've uploaded a video clip of the startup noise