The following cars represent the most technically advanced available.
The 2014 Volkswagen Jetta TDI offers basic transportation at a bargain and an excellent engine, but techies will want to hold off for the improved 2015 model.
With solid cabin tech, the 2014 Chevrolet Cruze Diesel competes well with compact sedans and gets stellar fuel economy, but high initial cost and the price of diesel eat into the savings.
Despite some very minor quibbles, the 2014 BMW 535d xDrive delivers exceptional quality and feature content on all fronts, from online cabin tech to fuel economy to driving satisfaction.
Brian Cooley runs down a list of the five brawniest four-cylinder engines in cars today.
The 2014 BMW 328d xDrive Sports Wagon combines 40+ mpg diesel efficiency, the flexibility of a wagon, and the thrills of a driver's car.
Featuring excellent fuel economy and a generally comfortable and easy-driving character, the 2013 Mercedes-Benz GLK250 makes for a useful all-around vehicle, good for the daily commute and family road trips.
The 2014 Audi A7 TDI includes some of the best connected tech available today in an automobile, and those inclined to put up with a few diesel drivetrain quirks will be rewarded with significantly higher fuel economy than from the gasoline equivalent.
BMW considers which models to offer as four cylinder diesels in the U.S.
Volkswagen's new hybrid system in the 2013 Jetta is a winner, delivering good driving characteristics and excellent fuel economy, but the cabin tech lacks features for a car in this price range.
Automotive News reports on new four-cylinder engines for U.S. cars from Mercedes-Benz.