Vehicles and the Emissions They Produce
Emissions from today's vehicles are lower than ever before, and the U.S. emissions standards are the most stringent in the world. However, as the number of vehicles on the road and the miles that they are driven each year continue to increase, vehicle transportation still contributes to air quality issues.
Sources of Auto Emissions
The power to move a car comes from burning fuel in an engine. Pollution from cars comes from by-products of the combustion process (tailpipe exhaust) and from the evaporation of fuel during the refueling process and from the vehicle fuel system.