Alyce,
There's quite a few owners that have reported air loss from the earlier (2001-2003) chrome rims. You didn't say if you had the chrome, but I'm assuming you do. Apparently the chrome on those rims, in some cases, starts to peel/flake and causes a build up of tiny pieces on the edge of the wheel. The best thing to do is have the tires taken off the wheels and have the complete edge of each wheel sanded and smoothed down to where the tire will seat properly and not loose air.
Oh yea,
WELCOME to the forum.
