What is SPN 2623 FMI 8 & How to Solve It?

What is SPN 2623 FMI 8:

SPN 2623 FMI 8 indicates a low voltage condition in the Fuel Pressure Sensor Circuit. FMI 8 means that the ECM is receiving a voltage signal from the fuel pressure sensor that is lower than expected, which can cause inaccurate fuel pressure readings and affect fuel delivery to the engine.

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Why This Happens:

• Faulty fuel 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 misinterpretation of the sensor’s signal.
  
  

How to Fix It:

1. Inspect the fuel pressure sensor for any visible damage or malfunction.
   
2. Test the sensor’s voltage and resistance to ensure it is within the expected range.
   
3. Check wiring and connectors for visible damage or corrosion.
   
4. Replace the faulty fuel 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 pressure sensor and wiring for damage.
  
• Perform routine fuel system maintenance to ensure proper fuel pressure.
  
• Keep connectors clean and free from corrosion.
  
• Perform diagnostic checks to monitor fuel pressure system health.
  
• Clue’s Fuel Management services help monitor fuel pressure levels and detect issues before they affect engine performance.