Water in Fuel Indicator
Indicates the presence of water in the fuel system.
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)
Your vehicle's computer has detected water in the fuel, which can cause major engine issues if not addressed.
What the computer is actually seeing
The system monitors the fuel conditions using a sensor that detects water contamination in the fuel filter.
What a healthy reading looks like
Sensor should read 0% water volume. 0.5% or greater triggers the code.
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 fuel filter for clogs. Replace if dirty and retest code.
- 22. Inspect the water-in-fuel sensor wiring for damage or corrosion. Repair if necessary.
- 33. Test the water-in-fuel sensor using a multimeter; expect 0V under normal conditions. If readings differ, replace the sensor.
- 44. If the issue persists, drain the fuel tank and inspect for water contamination; replace contaminated fuel.
Common causes
- Clogged fuel filter
- Defective water-in-fuel sensor
- Fuel contamination during refueling
- Faulty wiring or connectors to the sensor
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's best to address it soon as water can cause fuel system damage and drivability issues.
Will this code come back after clearing it?
Yes, if water is still present in the fuel system, the code will return.
Why does this code sometimes pair with SPN 1544?
SPN 1544 often indicates low fuel pressure or flow, which can be related to water contamination affecting system operation.
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