State tax filing

On the federal tax return -

For an energy-efficient vehicle tax credit

Click on Federal Taxes (Personal using Home & Business)
Click on Deductions and Credits
Click on I'll choose what I work on (if shown)
Scroll down to Cars and Other Things You Own
On Energy-Efficient Vehicles, click the start or update button

Or enter energy efficient vehicle in the Search box located in the upper right of the program screen. Click on Jump to energy efficient vehicle

 

For the Colorado state income tax return the form is DR 0617 Innovative Motor Vehicle Credit.  It should be located in the Colorado state program in the section for Other Credits.