Is it permissible to deal with the bank in paying for a car in installments with usurious interest, knowing that the amount is not available to pay off the loan?

The aforementioned transaction is forbidden by Islamic law because it is a loan with an increment, and this is usury (riba). If you engaged in it out of ignorance, we hope that you will not be held accountable, provided you were not negligent in seeking knowledge. However, if you were aware of its prohibition, then repentance and regret are obligatory upon you. You are not required to expedite repayment to the bank unless doing so would result in the cancellation of the usurious interest and you are able to do so. But if expediting the payment does not cancel the interest or you are unable to do so, then you are not obliged to expedite it, and sincere repentance is sufficient for you.