We just bought a 2001 Outback Limited for my daughter. It has 203,000 miles on it, ran fine for 3 days, then my daughter let the gas go below empty in cold weather conditions, she put 5 gallons of 87 oct gas in it and it started sputtering and making like a popping sound and the engine light came on. She made it home, so I filled it up with high octane and added some Heet gas dryer and injector cleaner and took it for a 10 mile ride on the highway it seemed to start to get better but then the check engine light started to flash. Kept driving and it started to get better but it was late so I pulled it in the garage for the night. Could there have been water in the bottom of the tank and it got into the fuel system and caused the engine light to go on ? I will drive it tomorrow and see what happens. Im hoping this is the problem, but was just wondering if what happened could cause the engine light to come on and what I should do next. Before we bought it it was not run for a while....just a few test drives the dealer said and the gas that was in it was probably old.