That is incorrect...a catch-can alone does not stop oil from seeping into either route and into the turbo and intake. Also, the catch-can has nothing to do with the EVAP route. The EVAP port is beside the PCV in front and connects directly into the v-cover apart from the PCV plate....note the 5/8" rubber plug in the final pic above. The EVAP flows through the v-cover separately from the PCV and exits beside the rear breather tube of the PCV duct at the rear.
There are two areas that can cause the loss of oil in the valve cover. Oil can seep into both the EVAP and PCV routes. So again, if there are no other causes of the loss of oil...you can be losing it through the EVAP route or the PCV route...or both. You can simply replace the v-cover and be done with it...or you can do the simpler of the two and do the EVAP reroute. If that fixes it...there is nothing wrong with the PCV route. But if the loss continues, perhaps at a slower rate then before doing the EVAP reroute, you have issues through both routes.
I decided to just do the EVAP reroute to see if this is where my issues were...and it was for the majority of oil loss. It costs less than $10usd for the bits to do the job. Until conditions worsen in the PCV route...I've bought myself some time to decide what to do next. It will likely be either the billet or OE valve cover. However, a billet valve cover requires a VTA catch-can and the EVAP reroute which I already have.
