Recently, at an Audi-sponsored event called the TDI Challenge, journalists driving 2015 Audi A3 TDIs recorded more than 800 miles on a single tank of diesel, driving between Albuquerque, New Mexico, and San Diego, California, reports the BBC.

There are many reasons to like the A3 TDI, and the fact it makes the most of its 13.2 gallons of fuel is at the top of the list.

On the road, the mid-level A3 2.0 TDI reportedly feels similar to the Volkswagen Golf TDI, which is due to both sharing the VW Group's stiff modular transverse matrix -- the engines are transversely mounted. Despite the architectural similarity, the A3 comes off quieter, and more sophisticated and refined. What makes the A3 more sophisticated is namely the available 4G LTE connectivity; the faster connection makes Audi's Google Earth-driven navigation system more accurate and fascinating.

Front-wheel drive is the key to the A3 TDI's thriftiness. Official fuel economy ratings of 36mpg in the city and 43mpg on the highway are conservative considering the BBC's test car achieved 50mpg on the open road.

Best off all, Audi has given the A3 sedan a budget-friendly $29,900 base price - $30,795 with destination charge. For the price, the buyer takes home a 170-horsepower 1.8-litre turbocharged four-cylinder gasoline engine (or an optional 220hp 2-litre four), a six-speed automatic transmission and leather interior. If you want the Premium Plus with all the bells and whistles, including the turbo diesel, expect to pay $40,000. Buyers who upgrade to the 292hp S3 could spend upwards of $50,000.

While the small sedan is Audi's most affordable vehicle, its standalone greatness negates its modest starting price.

The Audi A3's turbo diesel engine provides hybrid-level fuel economy, plus the car has a great techno-upgrades, proving that motoring pleasure is not exclusive to big spenders.

The car maker sold 2,383 A3s in the U.S. during January, making it a close second to the top-selling Q5 crossover, according to the BBC.