kevin-L

So, occasionally when starting my c43 I hear a rattle noise coming from the engine bay area. It doesn't do it all the time, only when its been driven for a while, then turned off for an hour or so, then started up again. Cold starts sound fine. The car only has 6k miles on it, but I don't remember this happening when it was brand new, is this normal? I plan to take it to the dealer to get looked at but given that I can't reliably reproduce the issue I'd like some advice from here as well if possible. I managed to catch it on video tonight, you can hear the rattle for a split second. Sometimes the rattle lasts longer, like 2 seconds, sometimes it doesn't happen at all.

Spaggettio

hey i would go back to the dealer that deffinately is not normal. my car 26000kms never heard that.

kevin-L

So the tech at the dealer listened to the video and said it was something to do with oil pressure building and that it's totally normal, but does anyone else's car make this noise?

jonathan358

Same thing occasionally happens to my car. I have the performance exhaust in which it would fk around with the exhaust flaps so I think it has an effect on the engine RPM. This makes my exhaust note change from high to low to high, not a smooth growl... Hopefully it isn't anything important and is just the way the car is made.

JohnnyC

Ok so ya'll need to look up the M276 rattle. its essentially the same engine but without the turbos.

kevin-L

So I looked up the M276 rattle and that definitely seems to be what it is. It seems like for the non-turbo engines, there's a bulletin with a fix for it. What should I say to the dealer to get them to fix it? Or do you think I should just leave it since it seems to not be something that would cause damage over time?

JohnnyC

Definitely don't leave it. Bring it up and say you want the sound fixed. There may be technical service bulletin for the C43, not sure as I am not a technician.

I will say this though with my own experience, when I did my first oil change (on my used car) i had the oil level set above minimum. The rattle sound appeared for me. I fixed it by filling closer to max.

Blackhead Kings

Did you fix this?????

Cosworth2000

Check your oil level to make sure it's at the right level. If your car is parked on an angle over night, that can sometimes cause this but with a young engine, it should not. Just like the C63 engines, you have to make sure your oil is always at the right level.

kevin-L

I had service A done on the car a few months ago and haven't heard the rattle since then.

W205C43PFL

Wrong thread sorry.