CEL issue

[RLsnuffy]

My CEL came on the other day. The car still ran great. Then I remembered that I filled up with a new brand of gas because I was about to run out. I've always filled up with SuperAmerica gas, and this was the first time I filled up with something else. Anyway, last night I filled up with SA gas again, and today the CEL light went off. Is it possible my car just didn't like the other gas, and threw a code because it was used to SA gas? Just curious...

[Watts-Up]

I wouldn't find it hard to believe. I have used almost every main brand and the cars performance varies alot, never threw a code though. Find out what code it was, it will still be in the history until cleared.

[RLsnuffy]

Used my buddy's OBDII scanner and came up as P0128 - Coolant Temp Below Thermostat Regulating Temp. We recieved a recent cold spell here in MN (Like below zero cold), so I'm wondering if that's why it threw the code. The light hasn't come back on since it went off the other day. Any ideas?