Direct petrol injection with spray-guided combustion, which Mercedes-Benz was the first car manufacturer to introduce in series production, has been developed further by the engineers into third-generation direct petrol injection with spray-guided combustion. The system pressure is now up to 200 bar and is variably optimised according to the engine's characteristic map. Completely newly developed piezo-electric injectors allow up to five injections per power stroke for the best possible mixture formation, while multi-spark ignition helps to ensure reliable combustion of the mixture. Further details on direct injection can be found in the section "Under the microscope: lean-burn mixture".

While the V6 unit is a naturally-aspirated engine, the new, technically similar V8 engine, which is due to be introduced during 2011 as the CLS 500 BlueEFFICIENCY, features biturbocharging for the first time, previously only seen in the 12-cylinder engine used in the S-Class. It too has direct injection but was designed for countries without sulphur-free fuel and is therefore run in a homogenous mode through the engine's entire characteristic map. Despite a significantly smaller displacement (4633 cc; previously 5461 cc), the eight-cylinder unit made considerable gains in terms of output (300 kW/408 hp; previously 285 kW/388 hp) and torque (600 Nm; previously 530 Nm). At the same time consumption has been significantly reduced. It is expected to achieve a saving in the region of 25 percent. Further details on the new engine generation can be found in the section "Under the microscope: innovative engine technology".