Not too bad but here's a few don'ts (mmm . more like try not to's heh):
-don't cut off any parts of the car. UNLESS you are trying to capture a specific part, then you wanna be really in close, like the headlights pic.
-don't center the subject in the middle (guideline of 3rd makes a stronger pic)
-don't fill the entire scene with the subject. subject needs to breath.
Of course rules and guidelines are meant to be broken and if you just don't care about photography then snapshots are good. And it only matters if they look good to you.
Man I really need to find a nice place to take pics of my car. I've been kinda learning about taking pics of cars from some IWSTI members. Here's some of theirs. Of course they do some post processing but they try to get the pic they want, right out of the cameras.
Linky to his sti photo thread on iwsti
Evo photog more landscape photog than car subject guy. But I like that one.
Anyways have fun.