Water-in-Fuel Sensor Fault
Indicates a problem with the water-in-fuel sensor or its circuit.
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 water-in-fuel sensor detects if there's too much water in the diesel fuel. If the system thinks there's water, it could cause engine performance issues.
What the computer is actually seeing
The ECM receives a signal from the water-in-fuel sensor that indicates either a fault in the sensor itself or that the sensor detects an abnormal water level.
What a healthy reading looks like
Sensor should output a voltage between 0.5V (no water) to 4.5V (high water).
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 the wiring and connectors to the water-in-fuel sensor for any signs of damage or corrosion. Repair if necessary.
- 22. With the ignition on, measure the voltage output from the sensor. It should be within the expected range (0.5V - 4.5V). If out of range, replace the sensor.
- 33. If the sensor appears to be functional, inspect the fuel for water contamination. Drain and replace contaminated fuel if necessary.
- 44. If all previous checks are good, use a scan tool to check for additional trouble codes or freeze frame data for any additional clues.
Common causes
- Faulty water-in-fuel sensor
- Short circuit in the sensor wiring
- Corroded connectors
- Contaminated fuel
- Faulty engine control module (ECM)
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
Moderately safe, but you may experience performance issues; fix it soon.
Will this code come back after clearing?
If the issue persists or is not fixed, yes, it will likely return.
Why does this code pair with SPN 1111?
Both codes relate to the water-in-fuel sensor and indicate issues with its functionality.
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