Bad Credit, But Need A Loan. What Can I Do ?

I recently bought a 2008 car. Since my credit was bad, my boyfriend co-signed. We thought he was the co-signer. It turned out the dealer put the loan in his name only. We have since broken up and he want me to remove his name from the loan. I have some of the money, but still need additional. Is there a way to pay the car company, then get a secured loan, since I have more than half of the money to pay for the car? What are my options?