2007 Subaru Impreza Engine, 2.5 SOHC, non-turbo, Automatic, with 51,000 original miles. Compatibility; should also fit similar generations of Outback, Legacy, and Forester.
As with just about every Subaru of this generation, the head gaskets are leaking. They are leaking externally, and the car is not overheating (nuisance leak). It is leaking just enough to smell oil on the exhaust occasionally but not enough to warrant adding oil in between oil changes.