Energy management in the BMW 4 Series Convertible.

Superlative performance translated into propulsion with maximum efficiency – the BMW 4 Series Convertible demonstrates the innovative breadth of BMW EfficientDynamics through an extensive package of technologies. For open-air driving pleasure: unmistakably dynamic, low on emissions.

ECO PRO mode.

ECO PRO mode helps drivers reduce their fuel consumption by up to 20 percent, depending on their driving style – according to an internal BMW fuel consumption study. The additional functions, coasting (with automatic transmission only), Route-Ahead Assistant and ECO PRO Route (both with Professional Navigation System only), deliver even more savings potential.
  • Using data from the Professional Navigation System, the Route-Ahead Assistant is able to recognise curves, built-up areas, speed limits and motorway exits, and even gives the driver tips to slow down in advance.
  • ECO PRO Route also ensures economical use of fuel. It offers you a route optimised for efficiency based on traffic volume, individual driving style and local conditions.


The entire vehicle design is testament to the BMW EfficientDynamics philosophy. The optimised, aerodynamic front apron and undercarriage feature innovations that reduce air resistance and fuel consumption. The front apron is a prominent design feature that embodies the BMW EfficientDynamics philosophy. The integrated Air Curtain channels air through two vertical air inlets and along the front wheel arches, with the accelerated air flow creating a kind of "curtain" on the outer side of the wheels. Then there are the Air Breathers, which channel the air flow at the front wheels. These innovative technologies reduce turbulence and air resistance, which in turn significantly reduce fuel consumption.
The flat undercarriage cover, which also shields the engine compartment, is an additional detail that greatly improves the car’s aerodynamics. These new trim elements are not only highly advantageous in terms of aerodynamics: they also improve the sound insulation and provide greater protection against rust.

BMW TwinPower Turbo.

In petrol engines, the BMW TwinPower Turbo combines a TwinScroll turbocharger with Valvetronic including Double-VANOS and High Precision Injection. In diesel engines, specially optimised turbocharger technology is combined with CommonRail direct injection and the newest variable turbine geometry.
In this way, BMW TwinPower Turbo significantly reduces the fuel consumption of petrol and diesel engines – while at the same time boosting power output across a wide range of engine speeds.

Auto Start-Stop.

Auto Start-Stop makes sure that fuel is only used when the car is actually driving. While waiting at traffic lights or in stop-and-go traffic, Auto Start-Stop saves fuel by switching off the engine as soon as the car is idle and the foot has been taken off the clutch (manual transmission), or when the driver brakes to a complete standstill (automatic transmission). 
A signal in the Info Display indicates that Auto Start-Stop is active. As soon as the driver shifts into gear (manual transmission) or takes his foot off the brake (automatic transmission), the engine immediately switches itself back on.
Auto Start-Stop never compromises driving comfort and safety, as it remains inactive if the engine has not reached its ideal running temperature, the interior has not yet been sufficiently heated/cooled, if the battery level is too low or if you are turning the steering wheel.
A central control unit restarts the engine if required, even when the car is at a standstill – for example, if the car starts to roll forward or if the windscreen becomes foggy. Auto Start-Stop can be switched off at any time with the push of a button.

Brake Energy Regeneration.

Every time you brake, kinetic energy is generated, and until recently this energy has gone unused. Brake Energy Regeneration takes advantage of this long-overlooked potential. It harnesses the energy that is generated whenever the driver brakes or takes their foot off the accelerator and turns it into electricity. This electricity is then used to charge the car battery. The intelligent energy management system means that the alternator no longer needs to run permanently, which reduces the strain on the generator. The result is reduced fuel consumption and increased performance – classic BMW EfficientDynamics.

Optimum Shift Indicator.

Optimal and perfectly-timed gear changes can help save fuel, particularly in urban traffic and over long distances. Optimal gear changes, less fuel consumption – the engine’s electronics system identifies the most efficient gear, based on road conditions and engine speed. An arrow lights up in the Info Display to show you when it would be more efficient to shift into a higher or lower gear. The system also recognises when you are accelerating fast, and will delay its recommendation accordingly until the engine speed is back up. Comparative tests have shown that vehicles with the Optimum Shift Indicator use around four percent less fuel.

Electric Power Steering.

Every time you turn the steering wheel, energy is consumed. But why should energy be consumed when you’re not moving the wheel? BMW Electric Power Steering is only active when it’s needed. Unlike conventional hydraulic steering systems, this solution from BMW only uses energy when you’re actually turning the wheel. When the steering wheel is static – e.g. when driving straight ahead along a motorway at high speed – the electric motor is inactive.