((a)) ** Definition of tier 2 emission standards** In this section, the term “tier 2 emission standards” means the motor vehicle emission standards that apply to passenger cars, light trucks, and larger passenger vehicles manufactured after the 2003 model year, as issued on , by the Administrator of the Environmental Protection Agency under sections 7521 and 7545 of this title.February 10, 20002000-02-10

((b)) ** Diesel combustion and after-treatment technologies** The Secretary shall accelerate efforts to improve diesel combustion and after-treatment technologies for use in diesel fueled motor vehicles.

((c)) ** Goals** The Secretary shall carry out subsection (b) with a view toward achieving the following goals:

((1)) Developing and demonstrating diesel technologies that, not later than 2010, meet the following standards:

((A)) Tier 2 emission standards.

((B)) The heavy-duty emissions standards of 2007 that are applicable to heavy-duty vehicles under regulations issued by the Administrator of the Environmental Protection Agency as of .

((2)) Developing the next generation of low-emission, high efficiency diesel engine technologies, including homogeneous charge compression ignition technology.