1991 740 2.3 non-turbo A/T

Hi, I've got a weird thing going on. This venerable old wagon is belching oil from the fill cap all over the cam cover, etc. The flame trap is clean. Does anyone know of any other posible points of obstruction?

Thanks in advance.

 

Is the nipple in the intake clear?
Oil cap seal good?
Maybe the vent box is clogged.