Audi has released additional details concerning the A4 g-tron set to be sold only as an Avant.
The new A4 (B9) is available across Europe in both Sedan and Avant body styles with a variety of gasoline and diesel engines, but those who would rather have the Avant-only g-tron version will have to wait until the end of 2016. It will be Audi’s second g-tron model after the A3 Sportback g-tron and will utilize an adaptation of the newly developed 2.0 TFSI with 170 PS (125 kW) and 270 Nm (199 lb-ft) of torque.
Audi says their engineers have modified the pistons and valves specifically for gas operation to enable an optimal compression ratio and there’s an electronic controller to reduce the high pressure of the gas that flows from the tank from about 200 bar to 5 to 10 bar in the engine. The A4 Avant g-tron needs less than 4 kg (8.8 lbs) of compressed natural gas (CNG) for 100 km (62 miles) and has CO2 emissions of less than 100 g/km. The 19 kg (42 lbs) tank capacity ensures a maximum range on CNG of more than 500 km (311 miles). Whenever there’s less than 0.6 kg of CNG in the tank, the car will automatically make the switch to gasoline operation and this will prolong range by an extra 450 km (280 miles).
To make refueling convenient, the car has both the gasoline and CNG filler necks under a single tank flap and Audi says that after refueling and whenever it’s cold outside, the car will start on gasoline and then immediately switch to CNG. The instrument cluster has two separate dials that show the fill levels of both tanks while the driver information system will display the fuel consumption when running on gasoline or CNG.
The Audi A4 Avant g-tron will come with four cylindrical CNG tanks mounted at the back along with a 25-liter gasoline tank. Compared to a conventionally-powered model, the g-tron doesn’t have a spare wheel well while the battery is repositioned from the trunk area to the engine compartment. It will be compatible with Audi’s own e-gas, a synthetic methane made from water and CO2 using green electricity to enable the model be CO2 neutral in operation.