P0331 Knock Sensor 2 Circuit Range/Performance (Bank 2)

P0331 points to a range or performance problem in Knock Sensor 2 circuit on Bank 2. The signal exists but does not fit expected knock-control behavior.

Code details

Generic OBD-II · P0

System: Ignition / Misfire
Code type: Generic (SAE / ISO controlled)
Standard: SAE J2012 / ISO 15031-6

Diagnostic boundary

A diagnostic trouble code reports that a monitored test failed. It does not prove one specific part is bad, and manufacturer logic can add vehicle-specific conditions.

Do not overlook low octane fuel, carbon deposits, or mechanical noise when diagnosing a Bank 2 knock sensor performance code.

Symptoms of P0331

Rough idle, shaking, or a stumble under acceleration.
A flashing check-engine light during an active misfire.
Power loss and higher fuel consumption.

Common causes of P0331

Worn spark plugs, ignition coils, or plug wires.
Fuel-delivery problems — injectors, pressure, or a lean/rich mixture.
Vacuum leaks, low compression, or a mechanical fault in that cylinder.

Useful checks before replacing parts

Compare Knock Sensor 2 signal with Bank 1 activity, timing correction, engine load, RPM, fuel octane, and freeze-frame data.
Inspect sensor mounting, connector tension, harness shielding, water intrusion, intake-area damage, and mechanical noise affecting Bank 2.
Confirm whether the signal is biased, too quiet, too noisy, or delayed compared with operating conditions before replacing parts.

Related OBD-II codes

These nearby ignition / misfire entries can help compare wording and pin down the fault area.