On the second generation OM 471, Mercedes-Benz dispenses not only with the wastegate valve for the turbocharger, but also with the boost pressure control. Together with the elimination of the EGR sensor and EGR control, this means that operation of the engine with its meticulously optimised thermodynamics is purely pilot controlled.
Controlling the engine in this way allows it to run even more efficiently. Precision pilot control of all variables results in an optimum efficiency factor without the added complication of individual control systems and their combination. The ingeniously devised emission control strategy, for example, replaces the individual control of exhaust gas recirculation and boost pressure that was customary in the past, and works far more effectively in this way.
At the same time, the engine has become even more robust owing to the omission of numerous components and parts. The fundamental idea here is perfectly simple and makes perfect sense: anything that's not fitted in the first place can't cause a malfunction.
Instead of using sensors with a linked system of control, Mercedes-Benz relies on various modes to assist with operation with, for instance, a cold engine, cold intake air or a cold exhaust aftertreatment system. Suitable modes have likewise been programmed for operation at medium and high altitudes, as well as for passive and active regeneration or regeneration when idling. With the exception of active regeneration, all the control modes are continuously variable, allowing the engine to be operated in an optimum efficiency range at all times.