CARS.COM — The Kia Optima was the big mpg winner in our 2016 Midsize Sedan Challenge, averaging 36.1 mpg. The Volkswagen Passat took second with 33.7 mpg, more than 2 mpg behind the Kia. Rounding out the top five were the Mazda6 (33.3 mpg), the Nissan Altima (32.9 mpg) and the Honda Accord at 32.7 mpg. We calculated fuel economy results by averaging our fill-up calculations (trip miles divided by gallons pumped at the end) with each car's trip computer output.
For the roughly 220 miles that we drove, each sedan returned an average speed of 45-46 mph, a brisk pace helped by stretches of open highway driving and little to no traffic along the street portions of the route. Because our average mph topped 45, you should really consider this more a comparison of highway mpg and not combined mpg.
How We Tested
We drove our nine model-year 2016 midsize sedans on a winding 220-mile route through rural Georgia and South Carolina to see which one gets the best fuel economy in the real world. Each contender had a four-cylinder engine. Six of them (the Accord, Hyundai Sonata, Mazda6, Altima, Subaru Legacy and Toyota Camry) were conventional engines, while the other three (the Chevrolet Malibu, Optima and Passat) employed turbochargers. The turbocharged engines varied highly in performance; two of them achieved the best overall fuel economy, while the other ended up near the bottom.
All but one of the sedans came with front-wheel drive; the exception was the Legacy, which comes with all-wheel drive.
In order to ensure the accuracy of our results, we used the following testing procedures:
- The cars were filled before and after the drive from the same gas pump.
- Each car was driven for the entire route in consistent conditions: air conditioning on, windows up and no use of cruise control. We also drove each car in the state it defaults to when started; no Eco modes or other fuel-economy aids were engaged by the drivers.
- The trip was divided into nine legs, so each of our nine drivers rotated through each car to account for differences in weight and driving style.