Found this while doing a carbon clean.
http://i.imgur.com/M6CMGK1.jpg
If the membrane for the oil separator tears, you could get a lot of oil sucked into your intake manifold. Apparently it’s from IM vacuum at idle sucking up oil from the sump.
Probably a cause for rapid carbon buildup in the intake valves. Just another thing to check for.
See http://audirevolution.net/forum/index.php?topic=3753.msg109003#msg109003