Adventures in car buying
Did you buy a make/model at a dealership that sells primarily that make, i.e. a Ford at a Ford dealership? Usually they all have a regional manager or a national customer care line you can call.
I had a buddy who bought a Jeep...the dealership tried to screw him over in the service department when it required major repairs that was covered on the warranty. They initially refused, but he called Jeep, and Jeep called that dealership and told them to replace the engine or have their name pulled off the dealership sign by the end of the day.
Car companies understand the nature of care sales and do not like it when their dealers pull stuff over on their customer because it hurts their brand. Raise hell at that level and you'll probably get the local manager in hot water and you will likely get your problem resolved. Good luck.