P0391: Camshaft Position Sensor B Circuit Range/Performance (Bank 2)
MediumPowertrainValve Timing
What does P0391 mean?
P0391 is a diagnostic trouble code indicating "Camshaft Position Sensor B Circuit Range/Performance (Bank 2)". The sensor or component is providing readings, but they fall outside the expected operating range. The part may be degraded, contaminated, or experiencing intermittent issues affecting valve timing performance.
Common causes
- Worn or contaminated valve timing component
- Vacuum leak or intake air leak
- Clogged filter or restricted flow
- Intermittent electrical connection issue
What should you do?
Schedule a diagnostic appointment at your earliest convenience. The vehicle is generally safe to drive short distances, but the underlying issue should be addressed to prevent it from worsening.
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Code P0391 can mean different things depending on your vehicle. TorqueBot gives you a diagnosis specific to your make, model, and year.