Are you legally required to leave your car when a police officer tells you to do so?
If you ask police if you are under arrest and they say no then I dont see a reason why you should?
Maybe if they have a warrant to search your car. Im more interested in the rules of random traffic stops when you are not under arrest and there is no warrant to search your car.
Im also interested if refusing to vacate your car gives police probable cause to search it?