[RickZie]

Hi, I'm new to the forum after recently moving from an M135iX F40 to 2020 M2 Competition DCT purchased from a BMW dealer. I love the car which I'm still getting used to. One thing I've noticed is that when starting from cold I don't hear anything other than the starter engage/disengage and the engine strike up. When the engine is warm I hear a slight tinny kind of noise for a short period after the engine starts around the time the starter disengages and again when I stop the engine. It only happens for around half a second, I let the dealers workshop foreman listen to it and when he heard it he said do you mean that noise, it's normal, I'd be more concerned if I could hear it all the time. I've watched a few Youtube vids showing M2 Comps starting and some of them exhibited a similar noise. Does anybody else own an M2 Comp that makes this noise, I'd try to video it but my car isn't currently at home and a video may not pick it up. At least I still have 17mths of the BMW warranty remaining....

[Maynard]

Exhaust valves are notorious for making some rattly noise, and I think they would be open (or more open) when hot vs. cold - could get s/b to start it for you while you stand outside to see if it is coming from the rear.

Edit - for clarification, the warm-up valves in the exhaust system near the muffler, not the ones that the camshaft drives.

[Moflow]

I know the sound of which you speak of. I've always assumed it was the exhaust valves rattling around in certain conditions.

[hlm2c]

Might be your wastegate rattling

[RickZie]

Originally Posted by Maynard

Exhaust valves are notorious for making some rattly noise, and I think they would be open (or more open) when hot vs. cold - could get s/b to start it for you while you stand outside to see if it is coming from the rear.

Edit - for clarification, the warm-up valves in the exhaust system near the muffler, not the ones that the camshaft drives.

Thanks for your reply, it sounds as though it's coming from the front under the engine...

[RickZie]

Originally Posted by Moflow

I know the sound of which you speak of. I've always assumed it was the exhaust valves rattling around in certain conditions.

This noise seems to be at the front under the engine, would an exhaust valve noise come from the rear.

[RickZie]

Originally Posted by hlm2c

Might be your wastegate rattling

I'm still getting to know my M2 Competition, would a waste gate rattle come from under the engine though it could be from the engine bay. I'm still trying to assess what's normal and what isn't as it still has 17mths BMW warranty remaining, The workshop foreman at Sopers BMW Lincoln said it was nothing to worry about, I'm not saying this is the case but I've experienced being told things are normal to save a dealer work and cost and often it will move an expensive fault outside the warranty period.