Powertrain
generic / SAE
P2344
Cylinder 9 Above Knock/Combustion Vibration Sensor Threshold
The knock or combustion-vibration sensor monitors the structure-borne noise of each cylinder. The signal level for cylinder 9 has stayed above the diagnostic threshold for an extended period, indicating either persistent knock or an electrical fault that biases the channel high.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number3 / 44
Possible causes
- Persistent knocking on cylinder 9 (low-octane fuel, carbon deposits, hot spot) high
- Sensor or wiring biased high by short or moisture medium
- Mechanical knock from bearings, piston pin or wrong torque low
Inspection / repair
- Difficulty: medium
- DIY: shop recommended
- Estimated cost: 120–1500 €
- Estimated time: 0.8–4 h
- Component: knock sensor
- Component: knock sensor wiring
- Component: fuel octane quality
- Component: cylinder 9 combustion
- MIL / check engine light
- emissions-relevant
Sources
References
sae:J2012