On the above mentioned vehicles the engine may misfire resulting in the "jerking" of the engine.
During this process the engine control lamp illuminates in the majority of cases and an error rate is saved in the control unit (misfiring).
The code P0301 signifies e.g. "Misfiring, cylinder 1".
If the compression, spark plugs and ignition coils have been checked and found to be in order, the problem may be caused by a faulty pin on the wiring harness connector for the engine control unit. The operation of the ignition coils can be checked, e.g. using an oscilloscope. If there is no signal here, the electrical wires can be checked for continuity with the aid of a multimeter.
In the case that a pin has broken off in the connector to the engine control unit, the vehicle manufacturer offers a repair cable with pin.
Important safety note
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