I am really unhappy... I had to buy a carbon monoxide detector which goes off every few minutes...
I had some exhaust smell coming in through the vents so I popped the hooded to have a look around the engine.
While looking around I noticed that the smell was very intense around the turbos so I has a closer look with a flashlight and I noticed a lot of oil was leaking out around the turbo.
I took it to the shop and they replaced the turbos.
Now I am starting to smell some exhaust from time to time and I hear a lot of ticking noises around the turbo and the exhaust.
BTW I have a 335d.