help!!!

put diesel in my gti last week, drained the fuel tank, been running fine all week, coming home today oil light flashing, looked at the engine, oil running out of the air filter box. Any one got an idea whats wrong

check the oil level and top up as required, clean out all your breather piping. its common for the breathers to become partially blocked then suddenly clear themselves dumping a load of oil into your airbox.