2017 Audi A5 Sportback g-tron The Audi A5 g-tron is powered by a 2.0 TFSI engine. It develops 125 kW (170 hp) of power and 270 Nm (199.1 lb-ft) of torque. With CO2 emissions of just 100 grams per kilometer (160.9 g/mi) (with S tronic), Audi is the first premium manufacturer to offer a gasoline engine in the B segment that achieves lower emissions than a comparable diesel engine.