What is SPN 791 FMI 10
- SPN 791: Refers to a fault in the fuel pressure sensor, indicating that the fuel pressure is either too high or too low.
- FMI 10: Indicates that the sensor is reporting an invalid signal due to a communication issue between the sensor and the ECM.
Together, SPN 791 FMI 10 signals a problem with the fuel pressure sensor, where the ECM is unable to get valid data for fuel regulation.
Why It Happened
This fault code is commonly caused by:
- A malfunctioning fuel pressure sensor.
- Wiring issues or poor connections between the sensor and ECM.
- A failing fuel pressure regulator.
- Fuel system leaks affecting pressure readings.
How to Resolve It
To resolve SPN 791 FMI 10:
- Inspect the fuel pressure sensor for faults and replace if necessary.
- Check the wiring and connectors for damage or poor connections.
- Inspect the fuel system for leaks or blockages.
- After repairs, clear the fault code and restart the engine to confirm the fix.
How to Avoid Before It Happens
To prevent SPN 791 FMI 10:
- Regularly inspect the fuel pressure sensor and fuel system.
- Ensure fuel lines are intact and free from leaks.
- Use Clue to monitor fuel pressure data and receive early alerts for sensor or system issues.
