Could be as bad as a head gasket. Hard to say. The leak may be from the coolant overflow tank. So, check the coolant level and if it is low in the radiator and high in the reserviour, replace the radiator cap.
If that does not work have a coolant system pressure test done to determine if there is a leak in the cooling system.
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Friday, November 2nd, 2012 AT 10:23 AM