January 14, 2016 — Volkswagen’s proposal to fix thousands of cars that cheat emissions testing has been rejected by environmental regulators in the United States.
The California Air Resources Board (CARB) rejected Volkswagen’s plan because the auto-maker did not explain how the fix would impact vehicle performance, emissions, and safety.
Volkswagen has proposed installing new SCR catalytic converters, according to the Wall Street Journal. The converters reduce smog emissions with a tank of urea-based solution that binds to nitrogen oxides (NOx) in the vehicle’s exhaust system.
Another option to fix the vehicles is simply updating the software. Because there is a trade off between performance and emissions, fixing the software could compromise performance and significantly reduce fuel economy.
The only remaining option is buying back the vehicles. Volkswagen is considering this option and says it would be faster than fixing the cars, according to Bloomberg.
The “defeat devices” were designed to reduce NOx emission to meet regulations during testing. On the road, the cars emit up to 40X the acceptable level of NOx. According to CARB:
“NOx emissions in California are the most important contributor to ambient ozone and a key contributor to fine particulate matter pollution, which is associated with premature death, increased hospitalizations, emergency room visits due to exacerbation of chronic heart and lung diseases, and other serious health impacts.”