You are wrong. As long as you registered your car in 2011 you could have claimed the diesel credit. Here is link to IRS http://www.irs.gov/Businesses/2011-A...of-02-10-11%29
Originally Posted by Sabersix
The tax credit expired on 31 Dec 2010. If you purchased your 2011 prior to that you could claim the $900 credit on your 2010 taxes (filed in 2011). Other than that there is no IRS tax credit.