studies indicate that fuel economy with ethanol-enriched fuels may decrease by about 2% in fuel-injected cars. so, cars that average 20 mpg on the highway with gasoline would average about 19.6 mpg with the ethanol-gasoline blends.
that's more than likely due to your location. with an increase in altitude, air density decreases, and, therefore, your vehicle's computer will automatically cut back on the fuel to air ratio. with this, you'll usually find a decrease in horsepower, but an increase in your mpg.sandman said:Since I moved out here where the blended gas is standard, my gas mileage actually went up 5%.