I have seen several 'faulty' electronic throttle actuators. What failed was the insulation on the wiring in the cable between the actuator and main harness. The insulation just crumbles to dust and any movement eventually causes 'electrical leaks' that usually send the car into the 'limp in ' mode. The EGAS computer constantly checks the voltage of the positioner variable resistor and the reference variable resistor, If they don't match it goes 'TILT' because it means the actual position of the throttle valve is not what the computer told it to be.

The root cause is faulty wire insulation!! Ford got hit with a very large lawsuit bill for a less expensive flaw they ignored. Maybe MBZ is next?