P2345 code meaning
Cylinder 10 Above Knock/Combustion Vibration Sensor Threshold
Powertrain system Generic code P23xx codes Check engine light
What P2345 means
P2345 is the knock code for cylinder 10, the last cylinder of a V10, so it appears mainly on engines such as Ford's 6.8L Triton truck V10, the Viper V10 used by Dodge, and the V10s of BMW M5/M6, Audi and Lamborghini. It sets when the knock signal belonging to cylinder 10's firing window stays over the calibrated limit; the module then keeps that cylinder's spark retarded. On a heavily loaded truck V10, towing, heat and low-octane fuel make real knock more likely, while on high-revving sports engines valve train noise can be mistaken for it. No manufacturer was found that documents P2345 publicly, and GM and Saab use P0324 for the same situation. Misfire on cylinder 10 is reported separately as P0310.
P2345 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 P2345
- Check engine light on
- Pinging when towing or climbing
- Loss of power
Common causes of P2345
- PossibleHigh load, towing or high intake temperature with marginal fuel
- PossibleCarbon deposits in cylinder 10
- Less likelyValve train noise interpreted as knock
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 10 combustion
What each part of P2345 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. |
| 45 | The exact fault in that area. |
What to do next
- Note P2345 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 P2345
What does P2345 mean?
P2345 means "Cylinder 10 Above Knock/Combustion Vibration Sensor Threshold". P2345 is the knock code for cylinder 10, the last cylinder of a V10, so it appears mainly on engines such as Ford's 6.8L Triton truck V10, the Viper V10 used by Dodge, and the V10s of BMW M5/M6, Audi and Lamborghini. It is a generic code, so it means the same on every make.
Is it safe to drive with P2345?
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 P2345 fail an emissions test?
Yes, it can. P2345 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 P2345 to fix?
Difficulty: medium. A typical repair takes 0.5 to 8 hours of work. This is a job for a workshop.
Will P2345 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.