Legal Question in Civil Rights Law in Pennsylvania

You have 50% ownership in the car. She cannot sell or otherwise dispose of the vehicle without your signature. You should atempt to work things out, and if this fails, you should see a lawyer. You can file an action for your share of the value of the vehicle, and if you are succesful, you can cause the sheriff to put the car up for auction and split the proceeds. This would take time and involve legal costs that would reduce the amounts you would receive from the sale, as well as attorneys fees. If you cannot work this out, you should see a lawyer who will explain the various options available to you.