Fuel Metering Unit Control Error
The engine control unit has detected an issue with the fuel metering unit.
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What it means (plain English)
The computer thinks the system that controls how much fuel gets sent to the engine isn't doing its job correctly, which can cause performance issues or poor fuel efficiency.
What the computer is actually seeing
The ECU is monitoring signals from the fuel metering unit. If it sees values out of the expected range for more than a specified time, it triggers this fault.
What a healthy reading looks like
Fuel metering unit should adjust the fuel flow based on engine demand, typically between 0 and 50 mg/stroke for diesel engines depending on load and speed.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Check for any visible damage to the wiring and connector for the fuel metering unit. Repair any issues found.
- 22. Test the fuel metering unit operation using a scan tool or multimeter to confirm it responds correctly to changes in engine demand.
- 33. Inspect fuel quality. Check for contamination or water in the fuel system; drain and replace as necessary.
- 44. If necessary, test the fuel pressure regulator for proper operation and correct pressures; make sure it holds steady at around 6-8 psi under normal conditions.
- 55. Clear the code and take the vehicle for a test drive to see if the code returns.
Common causes
- Faulty fuel metering unit
- Wiring issues or poor connections
- Fuel contamination
- Faulty fuel pressure regulator
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's moderately severe, so drive with caution but get it fixed soon to avoid performance issues.
Will this code come back after clearing it?
If the underlying issue isn't resolved, the code will likely return.
Why is this code paired with SPN 4567?
SPN 4567 typically indicates a related or cascading failure in the fuel metering process.
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