Oil in intake.

[TheCrippler]

I removed the section of hose between the air filter and the engine so i could replace the fuel filter. I noticed a Small amount of oil in the end of the intake still attached to the car and a tiny amount in the end of the section i took out. No oil up towards the filter end. Everything looked clean and dry.I changed the oil yesterday and accidentally slightly over filled it. I ran it for a minute to try moving oil through the system to see if the level would go down, (which it didn't). I ended up draining some oil out. Could the oil in the intake be from over filling and then running it for a few minutes?I read a few things about turbo seals going bad etc.2ct with only 45k miles on it. But who knows if this thing was maintained before i got? Nothing leaks though any where else as far as i can tell. The engine runs smooth, has plenty of power for what it is etc. Turbo sounds fine and I'm Good about warming it down before i shut it off.Any ideas? How concerned should i be?

[Rainman]

That is quite normal for turbocharged engines. I would guess what you are seeing is coming from the crankcase vent (small hose from valve cover to intake tube). While the engine is running the air in the crankcase will contain some oil vapor and for environmental reasons they typically route that air to the intake to be burned. Old industrial diesel engines and such used to just route that vent down the side of the engine to the ground.

The air is always flowing from the air cleaner housing to the engine so if the turbo seals were bad you wouldn't typically see the oil upstream from the turbo as it would be traveling against the flow of air. The oil would be in the aluminum tube between the turbo and the intake manifold if the turbo seals failed.

A catch can is an accessory that will collect this oil vapor and greatly reduce the amount of oil in the intake piping. This involves removing that small vent hose and routing it to a catch can then back to the intake pipe. The collected oil will need to be drained from time to time. The amount depends on the amount of vapor, etc.

This is what my catch can looks like. It's made my Mann+Hummell Model (Provent 200)
https://www.amazon.com/Mann-Hummel-6257511-Provent-200/dp/B01F2NZ6RQ

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Notice the small factory vent hose is replaced by the larger ones and are routed down to the catch can
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[TheCrippler]

I ended up doing the exact same thing about a month ago. The oil was definitely coming from the vent back into the intake. Its definitely collecting oil so hopefully things look more dry next time i look in there.