Why do high mpg European cars like the VW Lupo and the European model VW Passat fail our emissions tests?

The Volkswagen Lupo gets 75 miles per gallon. The new VW Passat European get about fifty. They are both diesel and they both fail our emissions test. Does anyone know what criteria they are failing.Why do high mpg European cars like the VW Lupo and the European model VW Passat fail our emissions tests?The more efficient the more melange U get. The EPA has required this poor efficiency to lower the NO2.Why do high mpg European cars like the VW Lupo and the European model VW Passat fail our emissions tests?
Different places have different pollution requirements. Europe views O3 (smog) as bad so they favor diesel engines over gas engine because they are cleaner for that. The US views NOx (makes acid rain and may cause cancer) as bad so we favor gas engines which are cleaner for that.



Diesels have a very hard time passing the current US emissions without adding lots of expensive things that people don't want to pay for.



Also test those cars using the US system and the mileage will be much lower. And people still complain that they struggle to get the sticker mileage in their own driving.Why do high mpg European cars like the VW Lupo and the European model VW Passat fail our emissions tests?Besides all the sane and rational arguments in favor of diesel, they are noisy, have poor low end torque, and stink. I wouldn't want my car %26amp; property sounding and smelling like a Grayhoung Bus Terminal.Why do high mpg European cars like the VW Lupo and the European model VW Passat fail our emissions tests?
they dont burn enough gas but i do all the time use ur finga on the motor and let go ps. try using aWhy do high mpg European cars like the VW Lupo and the European model VW Passat fail our emissions tests?they don't burn enough fuel for the oil companies