[AFBeefcake]

Replace the Coolant Temperature Sensor.
Its only like $25.00 at a subaru dealer, and take about 5 minites to change.

My car did that and about 12 weeks later the car started haveing trouble starting then it was cold. After I replaced the Coolant Temperature Sensor the car starts ever time on the first try.
I allso was geting bad gas millege before I replaced it.

For the price just replace it and get the code cleared.