Volkswagen is introducing a mid-size sedan that will get 42 miles per gallon on the highway without burning diesel or using a hybrid powertrain, the automaker announced Wednesday.

The Passat BlueMotion Concept, which will be unveiled at the Detroit auto show, is powered by a 1.4L four-cylinder EA211 TSI engine. It achieves its high fuel economy through direct injection and turbocharging, the automaker said.

The vehicle also uses a technology known as Active Cylinder Management that deactivates the valvetrain on two of the four cylinders when the driver applies light throttle to maintain city speeds. The engine is believed to be the first inline four with cylinder deactivation.

The Passat BlueMotion will debut at the North American International Auto Show beginning Monday. It's fuel economy