I do see them fail from time to time. When the coil fails, one of two things will happen. The engine will stop running or the car will die when the accelerator pedal is pused hard. There is not a service interval for anything but the plugs and the valve adjustment (15k)mi.

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Benzmac:
ASE CERTIFIED MASTER AUTO TECHNICIAN
SERVICE MANAGER FOR 14 BAY FACILITY
MERCEDES SPECIALIST 8 YRS
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