I had the same problem, first I was told it was the gas cap or bad gas. I took car to AutoZone and it would not code and the guy there also said bad gas. I finally took car to my Auto import repair he put a new big size code reader that showed that the car had two bad lifters in two different cylinders so the car wasn't mixing the fuel and really meant that I was running on 4 cylinders and the car a 6. I got the lifters replaced as well as replace all the wiring and spark plugs. I would go to a authorized shop with the latest code reader spend the $35 to $80 and get the right reading. P.S. my car was misfiring because of the bad lifters so I'm almost sure this your problem, that is why everybody say bad gas. I hope this helps
