The engine management light comes and goes. I got the fault code P13c2 Exhaust flaps malfunction. When I Chang the driving mode from confort to sport, the light go but after few days it comes back. Then I change driving mode back to comfort from sport the light will go again. No power loss.
SO all the time I changing driving mode to turn that light off.
Usually caused by the exhaust flap actuator., which requires replacing exhaust parts . Can be expensive .Dependant on your mileage and service history , could try Mercedes for a warranty claim or at least a contribution to cost