OBD-II code · Powertrain (generic)

P0331 Knock/Combustion Vibration Sensor B Circuit Range/Performance

Knock sensor B signal is in electrical range but plausibility check fails — typically a loose mounting, wrong torque, or sensor element drift.

Is it safe to drive with P0331?

Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.

Common causes

  • Most likelySensor loose
  • Less likelyGateway module routing CAN messages incorrectly
  • Less likelyCAN terminating resistor (120 Ω) drifted out of spec

Repair at a glance

Difficulty
Medium
DIY friendly
Often, with basic tools
Typical labour
0.5–2 h
Emissions test
Likely to fail
Parts involved
Knock Sensor

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.