Hello,
i'm having some problems with ratlle noise when the car is cold.
It is a European F48 sdrive20i with DKG transmission, 2018 built, 35.000km.
When the car is cold and I fire it up, it doesn't matter if it is in P mode or in D mode and I press the brakes, when I slightly touch the gas pedal I get some really annoying sound from under the hood. The same thing happens when I drive away slowly, this noise is there, but if I put it into sport mode with the button, the sound won't be there.
This sound is gone in a couple of minutes when the car gets hot.
Could this be a waste-gate on the turbo? The car has only 30.000 km and the funny thing is, that the service shop already swapped the turbo for the new one under warranty and the sound is still here.
Now they said they checked everything else and there is nothing they could do, except that I accept this sound when the car is cold..???
What else could it be???
I have also uploaded a file that I recorded:
- first there is a cold start up
- then I slightly rev the engine in P mode, the rattle happens
- I put the stick to D and step on the brakes, step slightly on accelerator and the rattle is there again
Please help me, I'm desperate finding a solution for this annoying sound.
Thank you for any advice!
Here is the recorded sound:
https://www.youtube.com/watch?v=0CGdTya-lVQ
Best Regards,
Mladen