It depends on what you mean by it was included in your Chapter 13. If you are still in Chapter 13 you have to obtain permission from the court to sell vehicle. If you have completed your Chapter 13 and the car was paid off through the plan then yes you have the rights as anyone else to sell the car (Make sure the title has been released to you from the financing company).
I agree with the attorney above. You may sell but you have to get court permission if you are still in chapter 13. Also you may want have your attorney call the creditor for an accurate payoff on the vehicle
Technically, the property vested back in you at the confirmation hearing. Therefore, you do not need a Motion to Sell personal property. However, many creditors and buyers are looking for one. Check with your lender (if you have one) and with the buyer or dealer to see if they want one.
[This communication is intended as general information and not specific legal advice, and this communication does not create an attorney-client relationship.]