P2346 code meaning
Cylinder 11 Above Knock/Combustion Vibration Sensor Threshold
Powertrain system Generic code P23xx codes Check engine light
What P2346 means
Cylinders 11 and 12 exist only on V12 engines, for example BMW's V12 in the 7 and 8 Series, Mercedes-Benz's M120 and its successors, and the V12s of Ferrari, Lamborghini and Aston Martin. P2346 reports that cylinder 11 has knocked above the threshold that the knock control allows in its crank-angle window. With twelve combustions per two crank turns the windows are short, so the module depends on clean crank and sensor signals to assign knock correctly; a fault on the bank sensor or noise from nearby parts can shift the blame. No manufacturer was found that publishes P2346; GM and Saab file a lone knocking cylinder under P0324. Retarded spark on one cylinder costs some power, but continuing knock can destroy the piston.
P2346 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor0.5 to 8 hours
- Clears after repairAfter a drive cycle
Symptoms of P2346
- MIL on
- Slight loss of power
- Possibly audible pinging
Common causes of P2346
- PossibleDeposits or hot spots in cylinder 11
- PossibleFuel below the required octane rating
- Less likelyDisturbed crank or knock sensor signal shifting the cylinder assignment
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Knock sensorKnock sensor wiringCylinder 11 combustion
What each part of P2346 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 3 | Area: ignition system or misfire. |
| 46 | The exact fault in that area. |
What to do next
- Note P2346 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P2346
What does P2346 mean?
P2346 means "Cylinder 11 Above Knock/Combustion Vibration Sensor Threshold". Cylinders 11 and 12 exist only on V12 engines, for example BMW's V12 in the 7 and 8 Series, Mercedes-Benz's M120 and its successors, and the V12s of Ferrari, Lamborghini and Aston Martin. It is a generic code, so it means the same on every make.
Is it safe to drive with P2346?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P2346 fail an emissions test?
Yes, it can. P2346 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P2346 to fix?
Difficulty: medium. A typical repair takes 0.5 to 8 hours of work. This is a job for a workshop.
Will P2346 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.