I´m using regular gas now, I tried using the highest octane but it didn´t make any difference, I think the backfiring and the other problem are going to be related when the problem is found, the dealer has given me some stupid answers on this problem too, like it might hang on the throttle if I´m running low on fuel, like a 2 stoke does like speeds up when its running out of gas, stuff like that, great answer huh, i´m going to give them 1 more try then I´m getting a district person involved.