N54: Oil leakage above exhaust manifold

Hello,
Since a couple of days, I have experience some smoke coming from the engine bay and a little oil spillages under the car after longer parking.

After short investigation I have noticed some oil on the collecting sheet above the manifolds and directly suspected the valve cover gasket. So I changed the entire cover including the gasket. During disassemble of the old cover some bolts at the corner of cylinder 6 had some oil on the thread and the gasket looked brittle. That's it I thought, but after reassemble and first test ride, there was smoke again coming from the engine bay. And the cover sheet above the manifolds shows oil again....
Has anyone experience an oil leakage at this spot?I have no clue where it is coming from. Looks a bit like it's bubbling out of the fixture bolt.


Thanks

Tobi

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