Subaru Problems? Ask a Mechanic for Answers ASAP
Check all fuses. Also do a compression test on the bank that is misfiring, you could have dropped valve guides.
The OBD-II data link connector on this MY Subarus doesn't give you much to work with. Basically the only thing you can check without a scope is voltage (pin 16) and ground (pins 4 and 5). Does the check engine light come on when the ignition is first turned on? Does it turn off once the engine starts?