P0331 — Knock/Combustion Vibration Sensor B Circuit Range/Performance

P0331: Knock/Combustion Vibration Sensor B Circuit Range/Performance — what it means, the affected system and what to check before replacing parts.

Meaning, symptoms, causes and checks

Knock/Combustion Vibration Sensor B Circuit Range/Performance. Basic catalogue definition; diagnostic details have not yet been reviewed.

Affected system: Powertrain

Symptoms

  • Check-engine light; engine may reduce performance under some operating conditions.
  • The B knock sensor performance is outside its expected range; this is a signal plausibility code, not proof of physical detonation.

Possible causes

  • Faulty knock sensor B, insecure mounting or damaged connector/wiring.
  • Interference or genuine combustion knock that changes expected sensor response.

What to check

  • Confirm P0331 and determine sensor B placement, including bank designation, from OEM diagrams.
  • Inspect the sensor's connector, mounting and nearby harness without disturbing hidden connectors unnecessarily.
  • Compare live knock-control response and reference signals using the vehicle-specific diagnostic routine.
  • Evaluate any actual metallic combustion noise or fuel/ignition issue separately.
  • Repair proven faults, then verify sensor performance under permitted conditions.

Also written as: P0331-00, P033100, PO331 (some scan tools add the fault-type byte, e.g. -00).