With it being a 99 year model and only having 17 thousand miles on it and if
your not driving the hell out of it (that's the cause of the poor gas
mileage) I'd take it back to the dealer ship where you bought it and start
bitching about it, they will probley take it in and look it over, check your
timing, look at the spark plugs and give it back to you and tell you there's
nothing wrong we could find, it must be your driving style, go back next week
and the next week,(again and again, until fixed) and if its truly not your
"driving style" it will finally one visit get fixed because they will get
tired of seeing you, its still under warranty and should be getting some what
close to what the gas mileage claims are. Don't let the service
writter,service manger scare you and try and tell you different, they will
tell you all kinds of crap, just stick by your guns and don't give in and
they really will find out why it doesn't the good mileage and make sure you
let them know you want this repair work covered under your warrenty.
Ron