Here is a quote from an automotive engineer giving a reason for excessive oil consumption with newer gasoline engines. Wonder if it is relevant to the excessive oil in the intake on the ecodiesel?
It is probably the PCV system that is doing it: Yet another "feature" you can thank the EPA for.
The vapors of the PCV system are considered a pollutant, so they get sucked back into the intake and burned during combustion. Since it is considered a pollutant, should the PCV hose become disconnected, the driver has to be "notified" somehow. Usually this is done with OBD and the check engine light, however, it is quite expensive to use actual physical equipment to monitor the PCV flow and make sure it is always connected.
The EPA allows the manufacturers a small loophole to save money and effort: design the PCV system in such a way that if it becomes disconnected, the engine will stall and be very hard to keep running. Awesome, I know, but we're kinda forced to do it if we want to sell cars.
So...now that we have PCV systems that flow so much, there exists a greater chance to suck oil vapor out of the engine where it can collect in the intake manifold and hang out. It also just gets sucked into the cylinders and burned.