Well... i dont have much of a clue on these things, i dad does tho... shall ask him later for you.
The best move now would be to keep a very close eye on the oil... check it every couple of days... check the drive where the car is parked for any leaks also.
It might be a head gasket (by the sounds of the exhaust it may be).
Get ur g/f sister to take it for a drive and follow her... when she puts her foot down, see if theres any smoke from the exhaust...
Another check... start it up and give it a few revs... make sure theres no blue smoke under hard acceleration (dont blow it up tho)
Ill ask for you when he appears home.
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