Yeah, my cam chain tensioners are leaking as well as my valve covers. I'll be posting pics on the valve cover replacement but I won't be touching the cam chain tensioners. I'll admit, I feel that is far too challenging. I don't know how to set my engine to TDC without pulling the bumper and I feel nervous about removing the cams!

 

Had a simillar problem on my 2004 A4. Change a busted boot rubber of the inner CV joint of the front drive shaft that was spilling grease onto the exhaust. The problem didn't go away. This annoying smell comes every time I'm idling.

A little thorough check reveled a broken breather pipe under the manifold and right next to where the oil dip stick connects to the engine. If it was not for the oily wetness around this area, it would have been a difficult diagnosis, as this pipe is really hidden.

Once this was replaced, the problem was solved.