While the engines in automobiles have been updated to clean them up, small engines in scooters, mopeds and other machines like lawn mowers and chainsaws have not been upgraded for the most part. Freescale Semiconductor has developed a new integrated circuit-based exhaust sensor to facilitate this closed loop control on small engines. The IC-based sensors should allow closed loop control to be implemented at a much lower cost.
Some small engine manufacturers are already testing the sensor, although Freescale is not yet announcing who. The sensors are expected to be in production by the end of the year. Thanks to Derek for the tip!