i have a 99 ws6 (mm6) that has been sitting for a year and a half!

symtoms:
-Oil on the coolant overflow stick
-oil in the radiator
-Not a drop of oil on the dip stick
-Oil cap is a little milky
-On the highway it gets pretty hot, but when i turn the temp dial on the dash to hot (without the blower motor on) it cools right down.
-When i got on it hard out of a toll booth, it left a little oil smoke cloud!
it hasnt done it since.

Please let me know what you guys think! i thought maybe a head gasket. Will a compression test, and a radiator pressure test tell me anything? What is a leakdown test? how hard it a head gasket install?
thanks

 

Sounds like a head gasket alright.Do you get low on coolant?

 

i haven't seen any coolant losses!