One problem related to manifold/header/muffler/tail pipe has been reported for the 2002 Subaru Outback. The most recently reported issues are listed below.
2002 Subaru Outback (not sure which engine) - noticed coolant smell around November 2005; was told by the dealer that the head gasket was leaking - they could either add a gasket "conditioner"ã‚ã‚쳜 treatment" - or I could go with the replacement gasket for ~$3000 or so. This was not long after my 60k service, wherein nothing had been found wrong. I also noted fuel smells, which they noted might require new fuel line and fuel rail(?) to the tune of another ~$650 or so. I asked about recalls, and they hemmed and hawed - they finally told me that there was a recall on earlier series engines, but that mine was outside the recall group. I've since found hundreds, maybe thousands of similar complaints by owners of late-model Subarus. Some get the replacement, but the car never runs the same afterwards. Many only get a replacement out of Subaru after going to the district or even national level at Subaru of America.