Water in Fuel Indicator - High
Indicates the presence of excess water in the fuel system.
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What it means (plain English)
The system detects too much water mixed in with the fuel, which can harm the engine and fuel injectors.
What the computer is actually seeing
The engine control module (ECM) monitors signals from the fuel/water sensor. It checks for a signal corresponding to water content greater than the acceptable threshold (usually around 200-400 microamps for clean fuel).
What a healthy reading looks like
Normal water concentration should be below 100 ppm; warning at levels above 500 ppm.
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 fuel level and quality. Ensure there’s no water separation detectable visually in the fuel tank or filter.
- 22. Inspect the wiring and connectors to the fuel/water sensor for corrosion or damage. Repair as needed.
- 33. Test the fuel/water sensor with a multimeter; check resistance is within manufacturer specifications (normally around 1-5 ohms).
- 44. If the sensor shows failure, replace it and observe if the code returns after clearing.
- 55. If code reappears, inspect the fuel system for contamination that may have caused high water content and rectify before running the engine again.
Common causes
- Faulty fuel/water separator
- Contaminated fuel
- Failed fuel sensor
- Wiring issues or corrosion
Typical repair cost
$$-$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's not safe to drive as excessive water in fuel can cause engine damage and poor performance.
Will this code return after clearing?
Yes, if the underlying issue isn't resolved, the code will likely return soon after clearing.
What happens if I ignore this code?
Ignoring it can lead to injector damage, engine misfiring, and even complete engine failure.
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