The oil is being sucked up the CCV tube into the air inlet, and dripping the very bottom between the air inlet and main housing. It's not a lot that drips. I replaced the turbo a couple of years ago and the turbo I removed had silicone sealing that part. I believe the is a large o-ring that is supposed to be there.K&N = NO!
I assume the leak in question is around the compressor housing?
Actually, the compressor housing is under pressure when the turbo is spinning. The o-ring area sees pressure pretty much all the time (obviously more when boost is high). The only low pressure (i.e. vacuum) area is at the compressor inlet.
Could be a leaking oil seal on the comp side.
If it's normal to leak a little then I won't mess with it.
It only happens when I have my chip turned on. If I turn my chip off it does't drip. I have moved the CCV to under the truck and it no longer drips with the chip turned on.
I believe the problem was the increase in boost from turning on the chip that caused the K&N to suck more air, and it needed more air but it sucked more from the CCV inlet into the turbo inlet causing oil to drip.
I have sense removed the K&N and replace it with a Tymar like setup. I'll be putting the CCV back to stock to see if it is fixed.