(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 February 10, 2000 , by the Administrator of the Environmental Protection Agency under sections 7521 and 7545 of this title. (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 August 8, 2005 . (2) Developing the next generation of low-emission, high efficiency diesel engine technologies, including homogeneous charge compression ignition technology. ( Pub. L. 109–58, title VII, § 754 , Aug. 8, 2005 , 119 Stat. 828 .)