What is SPN 520355 & How to Solve It?

What is SPN 520355:

SPN 520355 refers to a problem with the Fuel Rail Pressure Sensor Circuit. This fault indicates that the ECM is receiving an abnormal signal from the fuel rail pressure sensor, which could lead to incorrect fuel pressure readings and affect fuel delivery, potentially causing engine performance issues such as poor acceleration or stalling.

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Why This Happens:

• Faulty fuel rail pressure sensor.
  
• Shorted or damaged wiring in the sensor circuit.
  
• Loose or corroded sensor connectors.
  
• Low fuel pressure due to a malfunctioning fuel pump.
  
• ECM misinterpreting the sensor’s data.
  
  

How to Fix It:

1. Inspect the fuel rail pressure sensor and wiring for visible damage.
   
2. Test the sensor’s voltage and resistance to ensure it is within specification.
   
3. Check connectors for tightness and cleanliness.
   
4. Replace the faulty fuel rail pressure sensor if necessary.
   
5. Inspect the fuel system for low pressure or pump issues.
   
   

How to Avoid It Before It Happens:

• Regularly inspect the fuel rail pressure sensor and wiring.
  
• Keep connectors clean and corrosion-free.
  
• Maintain stable fuel pressure and replace fuel filters as needed.
  
• Perform diagnostic checks to monitor fuel pressure and detect early signs of sensor failure.
  
• Clue’s Fuel Management services proactively monitor fuel pressure and sensor performance, preventing issues before they affect engine operation.