BlueEFFICIENCY is a range of green environmental technologies aimed at reducing carbon emissions and improving fuel consumption across the Mercedes-Benz range. As a part of the BlueEFFICIENCY strategy, Mercedes-Benz has replaced the Kompressor engine with the new CGI engine in the C-Class Saloon and Estate.

The Kompressor surpercharged engine was developed to boost a car's power and acceleration using a forced induction system. New innovations in engine development have produced the Charged Gasoline Injection (CGI) engine. The CGI engine uses homogeneous direct injection with high-precision piezoelectric injectors combined with turbocharged for an increase in output from a small displacement engine. Alternatively, the Kompressor engine used a supercharger which drew its power from the engine, thereby increasing the petrol consumption.

The CGI engine has reduced fuel consumption from 8.1L/100km (C 200 Kompressor) to 7.3L/100km (C 200 CGI). The CGI engine is also cleaner than its predecessor, expelling 171g CO2 p/km (C 200 CGI) compared with 200g CO2 p/km (C 2oo Kompressor). A reduction in engine noise and improved torque output are both benefits of the switch to CGI engines. The new CGI engine demonstrates Mercedes-Benz dedication to reducing the impact of its vehicles on the environment.