1.8T AEB (petrol) 1999 - Black engine oil in the air intake hose?

[anorak_ian]

Hi, I took the air inlet hose off to find black engine oil in side the throttle body (at the bottom) and in the hose (top and bottom) and also inside the inter-cooler where the hose pushes on to. Could this be a turbo oil seal gone?

At the highest point is the butterfly valve, surly no oil would come from there, would it?

[Peter D]

Very common. There are no Oil seals in the turbo as such. When the turbo is cold oil leaks from the bearing seals and gets picked up by the boosted air flow and deposited along the length of the pipe work. When hot it still leaks but a lot less as the bearing/seal fit is tighter.
Regards Peter

[anorak_ian]

Thanks for the info