The 3 Series gains the EfficientDynamics systems already seen on the 1 and 5 Series models.
This uses direct injection, active aerodynamics, stop-start, brake energy regeneration, gearshift indicator and low resistance tyres to boost fuel economy and lower emissions.
As a result, all petrol and diesel models gain power yet become more frugal at the same time. As an example, the best-selling 320d model now has 177bhp – up from 163bhp, yet sees combined fuel economy rise by 19% to 58.9mpg.
CO2 emissions fall by 16% to 128g/km, putting it in the lowest 18% benefit-in-kind tax band.
The engine also finds its way into the 520d where it returns 55.4mpg and 136g/km of CO2.
Elsewhere, the X3 range and the X5 3.0-litre diesel also gain EfficientDynamics while the X5 family grows with a new 3.0sd version. The 6 Series range has also gained EfficientDynamics and a new diesel model – the twin-turbo 635d with 286bhp.