P2346 — Cylinder 11 Above Knock Threshold
P2346 — Cylinder 11 Above Knock Threshold. A fault in the knock (detonation) detection. Short, gentle driving to a shop is usually possible. Typical causes: loose sensor mounting or incorrect torque, failed knock sensor, damaged knock sensor wiring or connector.
powertrain (engine/transmission)
Is it safe to drive?
Drive with caution Drive gently and avoid hard acceleration. With knock detection off, the engine is not protected from detonation — sustained pinging under load can damage pistons and bearings over time.
How to diagnose with an OBD scanner
- Read the code and freeze frame Connect an OBD2 scanner, confirm P2346 is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
- Check for companion codes and TSBs Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many P0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
- Inspect wiring and connectors Visually inspect the wiring harness and connectors related to the knock (detonation) detection for damage, corrosion, chafing or poor contact.
- Subsystem check Inspect the knock sensor connector and wiring — heat and vibration damage them often.
- Subsystem check Check sensor torque and mounting surface; an improperly seated sensor reads incorrectly.
- Verify the repair Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm P2346 does not return.
Approximate repair cost
Repair cost depends on which component actually failed. Typical scenarios for P2346 (parts and labor, USD, independent shop rates): Repair sensor wiring: $80–$250; Decarbonization service: $150–$400; Replace the knock sensor: $150–$450. Overall, fixing P2346 usually costs between $80 and $450. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.
Common questions
What is the most common cause of P2346?
The most common causes are: loose sensor mounting or incorrect torque, failed knock sensor, damaged knock sensor wiring or connector.
How much does it cost to fix P2346?
Repair sensor wiring — $80–$250; Decarbonization service — $150–$400; Replace the knock sensor — $150–$450. Exact cost depends on the root cause, your vehicle and local labor rates — a proper diagnosis is the cheapest first step.
How do I diagnose P2346 myself?
Start with a scan: confirm P2346, save the freeze frame and note any companion codes. Then inspect the wiring and connectors related to the knock (detonation) detection, and verify the suspect component against live data before buying parts.
What are the symptoms of P2346?
Drivers most often notice: Check Engine Light on, worse fuel economy, reduced power (ECM retards timing), often no audible symptoms.
Will P2346 clear itself?
Sometimes P2346 clears after a few drive cycles if the fault was intermittent — for example a loose connector or a tank of bad fuel. The underlying cause usually remains, so the code tends to return. Clear it once; if it comes back, diagnose rather than erase it repeatedly.
What does P2346 mean?
P2346 is logged by the onboard diagnostics when the knock (detonation) detection does not behave as expected. The official definition is “Cylinder 11 Above Knock Threshold”. This is a powertrain (engine/transmission) category code.
P2346 refers specifically to cylinder 11. On inline engines cylinders are counted from the front (belt end); on V-engines the numbering depends on the manufacturer, so check the firing-order diagram for your exact model. Location matters for the repair bill: some cylinders require intake manifold removal, which adds labor time.
This code does not appear from a single bad reading: the module must see the fault condition repeat under defined operating conditions before it turns on the warning light. The freeze frame captured with P2346 — engine load, rpm, temperature, speed — tells you exactly when the problem occurs, so reproduce those conditions when testing.
What causes P2346?
- failed knock sensor
- engine carbon buildup causing real detonation
- loose sensor mounting or incorrect torque
- low-octane or contaminated fuel
- damaged knock sensor wiring or connector
Common symptoms of P2346
- Check Engine Light on
- worse fuel economy
- reduced power (ECM retards timing)
- often no audible symptoms
- metallic pinging under acceleration
How to diagnose P2346
- Connect an OBD2 scanner, confirm P2346 is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
- Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many P0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
- Visually inspect the wiring harness and connectors related to the knock (detonation) detection for damage, corrosion, chafing or poor contact.
- Inspect the knock sensor connector and wiring — heat and vibration damage them often.
- Check sensor torque and mounting surface; an improperly seated sensor reads incorrectly.
- Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm P2346 does not return.
How to fix P2346
Start with the cheapest and most common causes before replacing expensive parts:
- Repair sensor wiring — $80–$250
- Decarbonization service — $150–$400
- Replace the knock sensor — $150–$450
How much does it cost to fix P2346?
Repair cost depends on which component actually failed. Typical scenarios for P2346 (parts and labor, USD, independent shop rates):
- Repair sensor wiring: $80–$250
- Decarbonization service: $150–$400
- Replace the knock sensor: $150–$450
Overall, fixing P2346 usually costs between $80 and $450. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.
Can you drive with P2346?
Drive gently and avoid hard acceleration. With knock detection off, the engine is not protected from detonation — sustained pinging under load can damage pistons and bearings over time.