The average American emits 4.6 metric tons of carbon dioxide per year by driving a passenger vehicle. This number does not include the CO2 equivalent emissions released through the extraction and creation of gasoline. The emissions created before the fuel is even in the vehicle can range from 3.35-6.7 pounds per gallon. An average passenger vehicle can hold 12 gallons of gas. This means that every time you fill your gas tank up, you emit between 40.2 and 80.4 pounds of carbon dioxide before you even pull away from the pump.