Diesel vehicles may be making a comeback. Diesel engines are more powerful and fuel-efficient than similar-sized gasoline engines (about 30-35% more fuel efficient). Plus, today's diesel vehicles are much improved over diesels of the past.
Improved fuel injection and electronic engine control technologies have
- Increased power
- Improved acceleration
- Increased efficiency
New engine designs, along with noise- and vibration-damping technologies, have made them quieter and smoother. Cold-weather starting has been improved also.
Today's diesels must meet the same emissions standards as gasoline vehicles, and advances in engine technologies, ultra-low sulfur diesel fuel, and improved exhaust treatment have made this possible.
Although emissions of particulates and smog-forming nitrogen oxides (NOx) are still relatively high, new "clean" diesel fuels, such as ultra-low sulfur diesel and biodiesel, and advances in emission control technologies will reduce these pollutants also.
Excerpted from http://www.fueleconomy.gov/feg/di_diesels.shtml