607 2.2 HDi exhaust fumes under bonnet

[Rudy]

Hi,

Bought my 54 plate 607 2.2HDi Auto a few days ago.
The enine bay is (actually was - already cleaned it) covered in black soot.
There are exhaust fumes rising up from between the back of the engine and windscreen. Is there a common area where these leak?

Any help much appreciated.