Hey there! I see you posted a couple months back, but I am having a similar issue, only with more problems, maybe? Since the day I drove my '16 Forester XT off the lot back in November, I have experienced dropping RMP's when applying the brake and/or the car will lurch forward 5 or 6 times at stop signs/lights. Only died one time last week. This has happened 90% of the time and I learned to just not apply the full on brake, but more eek my way to stops. Dealer has the car now and just can't seem to find the culprit...BUT...I had a seat cover replaced at another automotive center and asked them to just check it out while they had it and see if they could come up with anything. They found the PCV valve to not be functioning well, oil in the line (I think the same as the one you are describing) and a filthy dirty throttle body. And they found an old stored code P1603 of stalling AND they could replicate the problem. Well, then!...I was instructed to take it back to the Dealer (by the dealer service department) as it's still under Subie Warranty and to not let anyone touch a thing or else the warranty will void. I took the vehicle and the detailed diagnostic report to them on Friday to be worked on this Monday morning. Well dammit if they couldn't replicate the problem or find any old stored codes. I inquired if they checked the PCV valve and throttle body grime and of course I got the "well, yah, but that's normal for a turbo to kick out some grime, it's still not the problem". So, he was gonna take it to lunch that day and dink around with it. I took the initiative to pay $150 for a diagnostic check, they found the problem, and Subaru is fighting it all the way. Long story short, check your PCV valve and throttle body. Have you had any drive problems like I listed?