The small letter ‘d’ in the BMW model names stands for a difference with big results: every BMW diesel engine – whether four, six or eight-cylinder – delivers refined power and superb fuel efficiency.
The diesel engine transforms the chemical energy contained in diesel into mechanical energy. While petrol engines compress a mixture of air and fuel and ignite it with a sparkplug (externally-supplied ignition), diesel engines first compress pure air, which causes it to heat up. The fuel is later injected directly into the combustion chamber and ignites itself (self ignition). The direct injection with common rail technology enables the precise control of the ignition process, an even increase in pressure and the targeted burning of remaining soot particles by post injections. This minimises burning noises, makes running smoother and reduces emissions.
The high compression ratio and pressure deliver generous torque even at low speeds and ensure efficient fuel combustion and thus lower consumption. Modern turbo technologies like the two-stage charging in the Variable Twin Turbo also increase the spontaneous power delivery and, in combination with modern automatic transmissions, minimise the response delay at low speeds. Thus BMW diesel engines combine the typical BMW dynamics and sportiness with smooth and refined running, low consumption and excellent acoustics.
The four-cylinder diesel in the BMW 3 Series Sedan 320d EfficientDynamics Edition, with 120 kW (163 hp) offers a powerful engine and a temptingly low average consumption of 4.1 litres of diesel per 100 km. The common rail injection technology ensures maximum running smoothness; and the BMW BluePerformance technology means BMW diesel engines already fulfil the EU6 emission norm that only come into effect in 2014.
The BMW 740d Series six-cylinder diesel engine in the BMW 7 Series Sedan boasts an impressive 225 kW (306 hp) and a torque of 600 Nm. Thanks to innovative TwinPower Turbo technology the vehicle can be started at just above idling speed and has an electronically-controlled top speed of 250 km/h. The combination of both a large and a small turbocharger enable a powerful start and thrust even at high speed.
Fuel consumption / CO2 emissions
Combined fuel consumption: 4.1 to 7.5 l/100 km
Combined CO2 emissions: 109 to 183 g/km
Further information about the official fuel consumption and the official specific CO2 emissions for new passenger automobiles can be obtained from the ‘The Passenger Car (Fuel Consumption and CO2 Emissions Information) Regulations’, which are available free of charge at all sales outlets and from this address: DAT Deutsche Automobil Treuhand GmbH, Hellmuth-Hirth-Str. 1, 73760 Ostfildern, Germany.