http://www.toyota-industries.com/environment/product/engine.html

"So that the diesel engines we develop will meet European exhaust emission regulations STEP III (Euro III), we have adopted the swirl control valve (SCV), which is a first among Toyota diesel engines, a diesel throttle, and the EGR gas electronic control with EGR cooler. Through these measures, reductions in NOx and particulate matters (PM) have been achieved."

Sixto
93 300SD 3.0