P0391 – BMW DTC

BMW DTC P0391 – Camshaft Position Sensor ‘B’ Circuit Range/Performance (Bank 2)

DTC P0391 meaning on BMW

The DTC P0391 code on a BMW indicates an issue with the Camshaft Position Sensor ‘B’ Circuit Range/Performance on Bank 2. This means that the signal from the camshaft position sensor on the second bank of the engine is not within the expected range or is not performing as it should.

BMW DTC P0391 symptoms

Symptoms of a DTC P0391 on a BMW may include:

• Check Engine Light illuminated
• Engine running rough or misfiring
• Reduced engine performance
• Difficulty starting the engine
• Engine stalling

BMW DTC P0391 causes

Common causes of a DTC P0391 on a BMW include:

• Faulty camshaft position sensor
• Wiring or connector issues in the camshaft position sensor circuit
• Engine timing out of sync
• Engine mechanical problems

BMW DTC P0391 seriousness

The seriousness of a DTC P0391 on a BMW depends on the underlying cause. Ignoring this code can lead to further engine performance issues, potential damage, and increased fuel consumption. It is recommended to address this code promptly to prevent any long-term damage.

How to diagnose DTC P0391 on BMW

To diagnose a DTC P0391 on a BMW, you can follow these steps:

1. Use a diagnostic scanner to retrieve the fault codes
2. Inspect the camshaft position sensor and its wiring for any visible damage
3. Check the engine timing to ensure it is correct
4. Perform a visual inspection of the engine components for any signs of wear or damage

How to fix DTC P0391 on BMW

To fix a DTC P0391 on a BMW, you can try the following:

1. Replace the faulty camshaft position sensor
2. Repair any damaged wiring or connectors in the sensor circuit
3. Adjust the engine timing if necessary
4. Address any underlying engine mechanical issues

How to erase DTC P0391 on BMW

To erase a DTC P0391 code on a BMW, you can use a diagnostic scanner to clear the code after the underlying issue has been resolved. This will reset the Check Engine Light and the code from the vehicle’s memory.

Recommended tools & DTC Scanners for BMW

Best Diagnostic App for modern BMWs: BimmerLink

Recommended Bluetooth adapter for Bimmerlink: OBDLink CX

Cable adapter for Bimmerlink: Enet Cable USB Type C

For older BMWs we recommend: Autel AutoLink AL319 (2024 version)

Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter

Some of the links on this page may be affiliate links, which means we may earn a small commission if you make a purchase. This helps us keep our DTC database up to date and provide valuable content for free. We only recommend products that we have tested and believe to be the best in their class.