BMW is a very popular luxury car and many people choose a BMW over other luxury cars due to the advanced features it comes equipped with which are not available in other cars. There are many sensors in your BMW that help in monitoring the vital parts of the car. The knock sensor picks up vibration and sound coming from the engine block and turns it into an electrical signal and sends it to the ECU. Go through the video to know the symptoms of a bad knock sensor in your BMW.
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