You said you've filled up four times, clear the code and it pops back up an hour later. It is more than likely not the cap, but like Chris said, pick up a venting gas cap for $4 and see if that causes it.
For your code to be coming on that quickly though I highly doubt it is the cap, but try the cheap stuff first.
BTW, did you ever get the specific code number?
Originally Posted by kerryann
I am not a lesbian but if I was I would do her.