If the bank sent you a title without a lien holder on it can you stop making payments on the loan and keep the car?

Your obligation to repay the loan is based on the promissory note you signed, and has nothing to do with a lien on the vehicle. Without a lien on the vehicle, the lender will be unable to repossess the vehicle, but they can still collect on the debt. They can also impose substantial penalties. Without a vehicle lien as collateral, most lenders will convert your auto loan into a signature loan at an interest rate of 12% or higher.