The 2011 BMW 328i sedan features a six-cylinder engine, but for 2012, BMW swapped in a smaller, turbocharged four-cylinder engine in an effort to improve fuel economy. The change appears to have paid off, as the 2012 328i sedan sees a significant bump in EPA fuel economy estimates compared with the 2011 model.

“The new EPA ratings are 24/36 mpg with the automatic, or 23/34 mpg with the manual,” says Automobile Magazine. “That's far superior to the previous 18/28 mpg.” In addition to the new engine, the 328i achieves these estimates with the help of “an auto start/stop system and active alternator management (a clutch keeps the alternator from spinning unnecessarily), which are standard in both 3-series models.”

Car and Driver writes, “These are, frankly, great numbers.” Compared with rivals like the 2012 Audi A4 and the 2012 Mercedes-Benz C250, Car and Driver also points out that the 240-horsepower 328i not only uses less fuel, but it’s also more powerful. The 211-horsepower A4 manages 22/30 mpg city highway, while the 201-horsepower C250 gets 21/31 mpg.

Compared with other upscale midsize cars, only the 2012 Buick Regal eAssist, Chevrolet Volt, Lexus HS 250 and Lincoln MKZ Hybrid earn better fuel economy estimates.

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