P2347Cylinder 12 Above Knock/Combustion Vibration Sensor Threshold
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- P2347 ends the per-cylinder knock series that starts with P2336 for cylinder 1; it is the code for cylinder 12 and thus appears only on V12 engines such as those from BMW, Mercedes-Benz, Ferrari or Lamborghini. The engine module has found that the vibration in cylinder 12's combustion window exceeds the threshold and is holding back that cylinder's spark. The J2012 title speaks of a knock or combustion vibration sensor, so the series is not tied to a particular sensor type. No manufacturer was found that documents P2347 publicly; the only bulletin seen for the series, from Stellantis, covers cylinders 1 to 4 of a four-cylinder engine, and GM and Saab use P0324. Work through fuel, deposits, plug and injector of cylinder 12 and check for mechanical noise.
- What you may notice
- Check engine light on
- Reduced power
- Possibly knocking under load
- Likely causes
- PossibleCarbon deposits in cylinder 12
- PossibleLow-octane or contaminated fuel
- RareCylinder 12 running lean (restricted injector)
- RareMechanical noise near the sensor of that bank
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €0 – €4,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.