I've had two or three episodes of the CEL being on and then going off. First time I was told "maybe gas cap not tightened properly", so I've been careful with that. Last episode, light was off by the time I got to the dealer, but history showed that the light had been on in the past. Service guy said it had PO171 error, but couldn't find anything wrong, so it must be BAD GAS and you owe us $104.50!! I called BS, but they insisted.------------- SO, anybody else have trouble with bad fuel or is this just some "dog ate my homework" crap that the service dept. is selling when they can't find the real problem??