Invalid Fuel Metering
The engine's fuel metering system is reporting an error.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The system that controls how much fuel the engine gets is not working properly, causing possible performance issues and poor fuel economy.
What the computer is actually seeing
The engine control module (ECM) detects fuel flow discrepancies based on the signal from the fuel metering components—this can happen due to incorrect voltages or sensor readings not matching expected parameters.
What a healthy reading looks like
The fuel flow sensor should output a voltage between 0.5V and 4.5V depending on flow conditions. If the voltage is continuously outside this range, a fault is reported.
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. Inspect the wiring and connectors to the fuel flow sensor for damage or corrosion. If found, repair and retest.
- 22. Verify fuel pressure with a gauge. It should be between 40-60 psi depending on the engine specs. If low, check the fuel pump and filter.
- 33. Check the voltage output of the fuel flow sensor while the engine is running. It should be between 0.5V and 4.5V. If not, replace the sensor.
- 44. If all previous checks are normal, consider the possibility of ECM issues, which would need advanced diagnostics.
Common causes
- Faulty fuel flow sensor
- Wiring harness issues (frayed or shorted wires)
- Incorrect fuel pressure
- Malfunctioning fuel pump
Typical repair cost
$$-$$$ (depending on repair and parts)
Related codes
Frequently asked questions
Is it safe to drive with this code?
Drivability may be affected; it’s best to fix it soon to avoid engine performance problems.
Will this problem come back after resetting the code?
If the underlying issue isn't fixed, the code is likely to return.
Why does this code pair with others?
Codes like SPN 1166 and SPN 1169 often indicate related issues in the fuel metering system, showing that they could be part of the same fault condition.
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