To amend the Internal Revenue Code of 1986 to modify and extend the credit for alternative motor vehicles, and for other purposes.

Amends the Internal Revenue Code to: (1) extend through 2012 the alternative motor vehicle tax credit for advanced lean-burn technology, hybrid, and new alternative fuel motor vehicles; (2) increase the amounts of such credit; (3) increase the threshold (the number of qualified vehicles manufactured by the manufacturer after December 31, 2005) for initiating the phaseout period for the eligibility of hybrid and advanced lean-burn technology vehicles for such credit; and (4) deny such credit to a taxpayer whose adjusted gross income exceeds $100,000 ($200,000 in the case of married couples filing jointly).