Your first option should never be, a law suit. Instead, your focus should always be on working on a solution. Unlike private owners, car dealerships are held to a slightly higher standard since they are the professionals. One would think that air bags would fall under the same regulations as seat belts, smog control or side mirrors. This could probably be best answered by calling a few reputable car dealerships in your state or a DMV, and asking them if the seller of a used vehicle is responsible for assuring that air bags are present and functional on vehicles that were originally equipped with them. If you get a unanimous "yes", then go and speak with the dealership where you purchased the vehicle. They will probably concede and "right the wrong". Remember, they have a reputation to protect. If you get a unanimous "no", then save your money and let it go. Never look at a law suit as a first remedy.