It seems like when I put Mobil gasoline in the Civic I get catalyst efficiency codes. Right after I put it in, the CEL comes on. I would think an oxy sensor or a converter was going out, but I put a different brand in and it goes away. I've had it happen from 2 different stations now, one off Kingery and one off 52 so I don't know if they would use the same distributor or not. It's such an odd happening I figure I would get the experts opinions on it.
