The modifications used on this model to achieve these low emissions include: a diesel particulate filter, improved oxidation catalytic converter, longer gear ratios, aerodynamic front grill, smaller door mirrors, subtle side skirts as well as other drag reduction features. (nextgreencar.com)
The emission control system features a close - coupled oxidation catalytic converter and a diesel particulate filter which is located in the firewall area. (topspeed.com)
Oxidation catalytic converter system and full - transistor ignition system adopted in the Type 4M engine (toyota-global.com)