One problem related to crankcase (pcv) has been reported for the 2001 Subaru Outback. The most recently reported issues are listed below.
2001 Subaru Outback at 90k after 2. 5 engine is started it rattles like the valve lifters are not getting oil lubrication. It last for about 10 minutes or until the engine temp gauge is in the normal range. It does this when the engine has been sitting more that 8 hours without starting. Changing of oil in crankcase, did not change the rattling sound. Upon taking the vehicle to the Subaru dealer, the service manager informed me this was a normal character feature of 2001 and newer Subaru's that had the 2. 5 engine and was caused by piston slap in the engine. The correct the noise the owner would have to have the engine rebuilt to stop the piston slap.