I haven't had the fuel problem, but I'm in an '04 (don't know if it matters). As for sound upgrades, hopefully you didn't get the Bose package, lol. I made the mistake of wasting $750 on this sub-par POS system. Already blew a speaker, and the system only has 350 watts distributed to "10" speakers. If you didn't get Bose, it will be MUCH easier to replace your speakers. From what I've read in the service manual, if you do have Bose (don't quote me on this), it looks like the Bose amp pulls in audio from the line out on the head unit, so that shouldn't be too hard to replace.