Last Feb. i hit a personal record score of 20mpg, no lie, my wife was there and saw it, we where shocked but have never seen it that high before and today still haven't. But that was due to the fact that i was driving down hill the whole way from the smoky mountains. Its possible that people get those mpgs, the worse I got was 9 mpg, but that was cuz there was a plug in the engine compartment that was loose, and every time i hit a bump the car turned off, took me 6 months to figure out that it was a small and simple fix as just connecting the plug back on correctly. Worse part was that i drove cross country from florida to california like that back in 2007, gas was not that bad though, thank God. My only guess for that issue is that i think the mechanic that saw the VX before i left unplugged something by accident or worse on purpose. You might want to check all your plugs, it could be something that simple. The plug that affected my mpg was the main wire harness that is inside the engine compartment, next to the right fender, there is 3 big-o plugs one over the other, the plug that was loose on mine, was the bottom one, and that one had my temp. gauge off when the plug was not plugged correctly.