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What does these codes mean: PO 331 PO 300 PO 306 PO 326 PO 323 PO 301 PO 330 PO 117

Answers from the Automotive Experts

Jessica Howe, Automotive Expert & Coach at


The codes you have are showing that you have multiple misfires in your cylinders, and that there is a knock detected in the engine. The misfires may be causing the knock, or both issue may be caused by something else. Further inspection and testing is needed. 

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