Ali AlShrouf

Hi to everyone

I have w211 2005 e240 2.6 engine
The problem is that I found oil inside the throttle body while I was cleaning it
and I have some oil leak in the face of the engine ( front side ) but i already changed the cover seal recently

1 : any one know why there is oil inside the throttle body ?
2 : how can I found the leak place ?

another question :

this part in the middle , is it pcv valve or not ??





Thank you