Zena, I would suggest that you contact an accountant. However, from what I know, you'll have to record the mileage that you use for business. Take that as a percentage of your total mileage, then take that percentage to find the amount of interest you can deduct.
For example, if you used your car for business 50% of the time and paid $1000 in interest, then you can claim $500 as a business expense.
For example, if you used your car for business 50% of the time and paid $1000 in interest, then you can claim $500 as a business expense.