Possible causes

– Faulty knock sensor
– Knock sensor circuit poor electrical connection
– Knock sensor harness is open or shorted
– Faulty Engine Control Module (ECM)

Tech notes

The P0331 code means that the Knock Sensor is not working properly. Problems with the knock sensor will not cause an engine performance problems. Replacing the knock sensor usually takes care of the problem.

When is the code detected?

An excessively low or high voltage from the sensor is sent to Engine Control Module (ECM)

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)
– Possible Lack/Loss of Power

P0331 HYUNDAI Description

The knock sensor is attached to the cylinder block. It senses engine knocking using a piezoelectric element. A knocking vibration from the cylinder block is sensed as vibrational pressure. This pressure is converted into a voltage signal and sent to the Engine Control Module (ECM).