So I just got back from a 1700 mile round trip vacation. While I was there, driving around in city traffic, CEL came on. I decided to dump a bottle of Chevron Techron in it, along with the Chevron mid grade for the drive home. 60 miles on IH-10, and code gone! I get back into town on Saturday night, and drive around town yesterday...code back again! Drive to work today on the highway 20 minutes.... code gone again! This is wigging me out. At this point, I'm ready to go full Scotty Kilmer and pour in a gallon of paint thinner on a half tank of gas to see if it helps dissolve any crud in the sensors or inside the CAT. Any ideas?