It's illegal to tamper with gas and diesel vehicles. Motor vehicles contribute to nearly half of air pollution in the U.S., emitting large amounts of fine particle pollution, carbon monoxide, hydrocarbon pollution, and nitrogen oxide pollution.
These pollutants are linked to a variety of problems, including respiratory symptoms such as irritation of the airways, decreased lung function, aggravated asthma, heart disease, and premature death in people with heart or lung disease.
Motor vehicles contribute nearly half of air pollution in the U.S., emitting nearly sixty percent of carbon monoxide, a quarter of hydrocarbon pollution, and nearly a third of nitrous oxide pollution.
Emission control devices installed on motor vehicles and engines are there to protect your health by reducing air pollution.