I agree that you definatly need to get in touch with the sales guy before your grace period is gone. If the guy is honest and apologetic about it, let them fix it and see how it goes. If he tries to feed you a line (lets see.. "all of them do that" or "you must have broken it because you're not used to driving"), take it back, demand they accept it back, threaten to get your lawyer in there, whatever you have to do. If they give even the slightest hint of trying to blow you off, get rid of the car and wash your hands of the whole experience. Then start hunting for another one

Others may feel differently of course, but I dont think you want to get stuck with a money-pit car...

-colin