Water in Fuel Indicator
This code 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)
The computer is detecting moisture in the fuel, which can cause engine performance issues and damage. This usually happens when fuel is contaminated or has absorbed water due to storage conditions or faulty seals.
What the computer is actually seeing
The onboard computer monitors the fuel system for water content levels. If the detected water level exceeds a specific threshold, typically around 0.03% (300ppm), it triggers this warning.
What a healthy reading looks like
Normal water content in diesel fuel should be below 0.03% (300 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. Inspect the fuel filter and water separator for signs of water presence, drain if needed. Decision: Is there water in the filter? Yes - proceed to step 2. No - this code may be a false trigger, monitor for reoccurrence.
Common causes
- Water contamination in fuel tank
- Faulty fuel conditioners or filters
- Leaking tank seals or fuel lines
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's best to avoid driving until the issue is resolved. Water in fuel can damage the fuel system and cause performance issues.
Will this code come back after clearing?
If water is still present in the fuel system, the code will reappear. It's crucial to address the source of the water.
Why does this code pair with other fuel-related codes?
Codes like SPN 823, SPN 825, and SPN 826 relate to water detection and fuel quality, which can indicate multiple issues in the fuel system.
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