I checked my m7 occ yesterday and it was empty! The last time I emptied it was at least a couple of months ago and it had the typical oily water. So, I checked the hose that goes from occ to the intake tube. The hose didn't appear to have an oily residue in it, I even sprayed some brake cleaner down it and nothing. So it doesn't seem that the oil from the occ got sucked into the intake stream. However, I did notice on my intake tube (stock) has some oil residue in it where the hose from the occ connects. I also opened my throttle body and there definite oil residue down in there. Any thoughts?

 

I had the same experience.
Bought the car and checked the OCC. Got the oil-water you described but last time I checked it was dry. Could it be the original owner never checked and I checked to soon?

 

Having the same issue with my Alta OCC. Oil level in the case is constant, no loose fittings, no obstructions in the hoses, and no leaks as far as I can tell. I'd thought maybe it was the summer heat, but am really at a loss to explain this one.