So, how do you prove that your car saves a lot of fuel in real-life conditions? You drive it around and you publish the results. We've seen a few of these tests lately, like one driving a Skoda around Germany and Austria, or a Peugeot 308 around Australia or the 50-liter test in Canada. Now, Audi has decided to show off the new base powertrain for the Audi A4 TDI, the 2.0 liter, 120 HP, 6-speed manual.

Eleven A4s started a trip yesterday that will see them go for 1,650 kilometers (1,025.26 miles) around Germany, Switzerland and Austria to prove that the official consumption figures of 4.1 liters per 100 km (57.37 U.S. mpg) for the extra-urban cycle, 6.7 liters (35.11 U.S. mpg) for the urban cycle and 5.1 liters (46.12 U.S. mpg) combined are accurate. The A4s are fitted with a fuel consumption gauge to help the drivers will know when they're light on the foot and can maybe stretch a few more miles from the tank. Find the complete details after the jump.

[Source: Audi]