When I changed out my diverter valves I noticed inside the right one there was oil. She doesn’t smoke, no decrease in oil level between changes. Could it be a small leak originating from the turbo? I was running K&N filters but the oil wasn’t red, looked like motor oil. Thanks in advance!
Another thought - you were wondering if you may have a small leak originating from "the" turbo. Well, your '15 S has two (2) turbos.
And, the same oil that lubricates your engine lubricates the turbos. That's one of the reasons not to exceed 10K miles between oil
changes. Keeping the turbo bearing lubricated is a severe operating environment. If oil is leaking from a turbo (intake side) and it's
getting into a blow off valve, it would seem that you'd notice some change in the oil level between changes.