P0391
Camshaft Position Sensor B Circuit Range/Performance Bank 2
Generic code
Ignition System
High severity
Moderate repair
Free on OBD DashX
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What P0391 means
- The fault code P0391 indicates that there is an issue with the circuit that controls the camshaft position sensor for bank 2. This may cause the engine to run poorly or not start at all.
Possible symptoms
- Illuminated check engine light
- Poor engine performance or stalling
- Rough idle or reduced engine power
- Difficulty starting the engine
Possible causes
- Faulty camshaft position sensor
- Wiring or connector issues in the circuit
- Failed engine control module (ECM)
- Timing chain or belt issues
Related parts
- Camshaft Position Sensor: The camshaft position sensor monitors the position of the camshaft to regulate fuel injection. Problems lead to stalling or car failing to start.
Possible solutions
- Replace the camshaft position sensor
- Check and repair any damaged wiring or connections
- Replace the engine control module (ECM) if necessary
- Inspect and repair any timing chain or belt issues
Free on OBD DashX
P0391 on OBD DashX
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