Seat Ibiza knocking combustion issue

Knocking combustion on a 2009 Ibiza? That sounds like pre-ignition, possibly due to carbon deposits. Have you checked the ignition timing? Does the error code point to a specific cylinder or knock sensor malfunction? Detonation can cause significant engine damage if left unchecked.

The error code relates to multiple cylinders experiencing misfires. I haven't checked the ignition timing myself, as I lack the necessary diagnostic tools. Could the knock sensor itself be faulty, triggering the error even without actual knocking?

Multiple cylinder misfires coupled with knocking points strongly towards the combustion chamber deposits being the culprit, especially considering the mileage. While a faulty knock sensor could trigger false positives, it's less likely to cause misfires across multiple cylinders. Given the symptoms, I would advise against further driving to prevent potential engine damage and suggest a professional diagnosis and cleaning of the cylinder heads.

Appreciate the detailed insights. Took it to a workshop as you suggested. They confirmed deposits in the combustion chamber causing pre-ignition. Chemical cleaning of the cylinder heads and related components seems to have resolved the issue. Total cost was 425€. Thanks again.