Emission Facts: Average Carbon Dioxide Emissions Resulting from Gasoline and Diesel Fuel - OTAQ - EPA

(not so?) interesting fact - each gallon of diesel produces 14.7% more carbon dioxide than each gallon of unleaded. That means a diesel that gets 45.9 miles to the gallon is the same as a "normal car" that gets 40 miles to the gallon. In spite of this, diesel is a better fuel for CO2 hating times - it is not uncommon to see diesels getting significantly more than a 14% increase in emissions.

Gasoline carbon content per gallon: 2,421 grams
Diesel carbon content per gallon: 2,778 grams
= 14.7% more CO2 per gallon

Emission Facts: Average Carbon Dioxide Emissions Resulting from Gasoline and Diesel Fuel - EPA