Can I deduct taxes paid in car purchased in 2016 on my 2018 file if I didn't deduct it on 2017 tax return?

[xmasbaby0 · Accepted solution]

No you cannot.  You can only claim sales tax you paid in 2017 on your 2017 return, or sales tax paid in 2018 on a 2018 return.  If you did not claim it in 2016 when you paid it, you can amend your 2016 return.  Sales tax is an itemized deduction and only helps if you have enough other itemized deductions to exceed your standard deduction.