[gigglesnirt]

there is nothing you can do now except sell the car or repair it, this is a main reason i dont go to used car dealerships, i, and many friends have been "shafted" frmo these guys, and sure, sometimes they will have a good car, but the bottom line if they have something you really want/need i would take it to a certified dealer, like if its a toyota, take it to a toyota dealership, tell them to do a full checkyup, it'll take about an hour, and cost 100$, but its a much better situation than your in now.