One problem related to blown head gasket has been reported for the 2002 Subaru Outback. The most recently reported issues are listed below.
Driving down the road in 2002 Subaru Outback smelt burning coolant. Then , started seeing a lot of smoke from the driver side engine hood area. Pulled over and found that the coolant was empty in the tank. Refilled with fresh coolant and continued down the road back home. Car was smoking all the way back. Took it to a shop, and found that the engine head gasket had blown. Mechanic replaced the head gaskets and machined heads. Cost $1700.