
You have this all mixed up. First, the debt forgiveness you are worried about occurs because your personal obligation to repay has been waived. Second, the income is not realized to the extent you are insolvent when it is forgiven, or you file for bankruptcy, which results in the debt forgiveness. The issuance of the 1099 is just that, it is not itself realization of income. If there is income associated, so be it. But your return will give your characterization. Now as to your question. If the vehicle is sold, and there is a deficiency, you still owe the debt, i.e., the deficiency. It is your personal obligation until you file for bankruptcy and are discharged from paying it. Think of it like this. I owe you $10. I can't pay. You grab $5 from me, and do it legally. I still owe you $5. I file for bankruptcy, the remaining $5 debt can no longer be demanded of me. So, I just had income of $5. But it is not taxable.