So i have this noise that appears after driving about 10km in city traffic. No sounds at all when the engine is cold, no errors, no slipping clutch or something similar. Only this annoying metalic sound when idling. Notes:

 

- if the revs are 1000 or higher the sound goes away

- the sound gets worse if i turn on the AC (?!)

 

you can listen here:

https://imgur.com/a/s777S6M

 

what should i do?

If there’s no difference to the way it drives and no warning lights flagging up then it could be something loose and the engine at idle revs is causing enough of a vibration that makes it noticeable, the AC raises the idle RPM ever so slightly that would increase the vibration a tiny bit which would explain it being noisier.

 

Personally I would get it booked in and checked over, it’s definitely noticeable on that 2nd vid so at least you’ve got good proof of the noise.

I went to a mechanic yesterday and he said the problem it’s the DMF. My car has 110k km, 10k since i bought it. He also told me that the clutches work very fine and smooth and there is no sign that they will fail soon.

so what I need to do is to change the DMF. Not sure if I should change the clutches now as well just to have everything new in there.