Good day, I drive a S320 CDI built in 2008 at 247000km engine OM642… And I have the following problem…and that’s standing while gasting and also during the ride usually so between 1500-2000 revolutions the car makes such a funny noise. I was so far in 9 different workshops and unfortunately nobody could help me any more. The turbo was suspected but this has neither game on the shaft nor is the one from the inside. I also did not have any power loss or black smoke The vehicle has often gone into emergency running yesterday replaced the AGR valve and now the vehicle is running much better but this noise or grinding or the air turbulence that arises there is still there and slowly gets on my nerves and so far no workshop could tell me what that is. When you stand in front of the engine you hear that comes from the right side of the engine. The MKL is not on and when reading out it shows no errors at all. n. And while driving the vehicle is jerking. I am currently at a loss. Did not find anything in the net that resembles the problem.. am currently at a loss I ask for help ???????????