B180 CDI 2007 Rattling noise

Hi to all!

I am new here and I am reading this forum from before.

I hope that writing in the English language is not a problem for you, because I don't know well the German language. I am also reading this forum by the help of google translate

I have Mercedes B180 CDI, 2007 year, 80 kW, 109 hp, W 245.207, with DPF, manual transmission, with 255.000 km on the clock.

Here is my problem described:

When I start the car (cold start) after 25-30 seconds I am hearing a weak rattling noise which is hard to be heard from the inside if there is any noise around but can be clearly heard if the hood is opened.

This noise is reducing after 2-3 minutes and maybe completely gone after.

After at least 15-20 minutes driving, if I turn off ...