Diagnostic procedure for electromagnetically operated valve drive of IC engine

摘要

A diagnostic procedure is described for the electromagnetically operated valve drive of an IC engine whose lifting valves are moved by solenoid actuators in oscillating fashion by the effect of two restoring springs directed against each other. The position of each lifting valve or of the armature operating this, which is guided in the actuator between two magnet coils in oscillating fashion, can be measured by a position sensor. First, a determination of the middle position of the valve is executed to which the operationally warm engine is shut down from a low operating point (like idle). Subsequently to this, at least the actuator of the valve to be diagnosed is completely shut off electrically so that after a certain time span inside of which this valve has ended its oscillating movement, its middle position is measured with the help of the sensor.