Enter the portion that is based on your car's value. Check the charts here - find your state, and it will tell you what you can deduct. Your car registration fee is deductible if it’s a yearly fee based on the value of your vehicle and you itemize your deductions. You can’t deduct the total amount you paid, only the portion of the fee that’s based on your vehicle’s value.
If the total ad valorem tax is based on the value of the car, you can deduct the total.