Just done an oil/spark plug change and I've come across a dip stick next to the intercooler. I take it this is the oil for the TURBO ? Does it not just run off the engine oil ? Why do you need a seperate dip stick ?

ALSO. I've noticed a little OIL discharge either side of a hose than runs from the bottom of the intercooler to the side of the turbo. What is this hose for ?

I'm new to the world of turbos and its all a little unknown. ANY technical info.would be greatfully received. (My motor is a UK `99 Impreza Turbo.

Thanks guys.