Water In Fuel Indicator
This code indicates the presence of water detected 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)
The computer is noticing that there is water mixed in with the fuel, which can cause the engine not to run correctly and can damage components.
What the computer is actually seeing
The engine control module (ECM) sees a signal from the fuel water sensor indicating a level of water that exceeds the designed threshold.
What a healthy reading looks like
Water content in fuel should be less than 0.05%. A typical sensor will trigger above this threshold.
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 water sensor for corrosion or damage. Decision: If damaged, repair or replace; if okay, move to step 2.
- 22. Check the fuel water separator and drain any accumulated water. Decision: If water is present, drain and clear; if no water found, proceed to step 3.
- 33. Test the fuel water sensor for proper operation (typically a resistance reading when submerged in water). Decision: If faulty, replace sensor; if functional, check fuel system integrity for leaks or contamination.
- 44. Assess the fuel quality. Consider a fuel sample analysis for water content. Decision: If contaminated, replace fuel; if clean, move to step 5.
- 55. Clear the code and road test the vehicle to verify if the code returns. Decision: If it returns, further investigation into the fuel system may be required.
Common causes
- Faulty fuel water sensor
- Contaminated fuel supply
- Leaking fuel lines or connections
- Improper fuel storage conditions
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive the vehicle with this code?
It's best to fix this issue soon as water can cause serious engine damage and affect performance.
Why did the code appear again after clearing it?
If the source of water in fuel isn't addressed, the code will return once the ECM detects it again.
Will repairing the fuel system prevent the issue from reoccurring?
Yes, fixing leaks and ensuring clean fuel will help prevent this code from coming back.
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