Oil smell after shut down. Sometimes at start up
 

2013 S All4 CM with 85k miles.

When I shut the engine off everything seems normal, but sometimes 5 minutes later there is a strong oil smell. It doesn't exactly smell like burning oil, more like just dirty crankcase oil. I'll get the same smell at start up sometimes. The car doesn't seem to use any oil and it doesn't seem to smoke either. I looked all over and cant find any leaks either.

I wonder if it's oil leaking from the turbo shaft that is collecting in the hot side of the turbo and is cooking, not actually burning.

Thoughts?