WATER IN FUEL
Indicates that there is 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 sensing water in the fuel, which can cause engine issues like misfires and stalling, and it's really important to fix right away.
What the computer is actually seeing
The ECM uses water detection sensors in the fuel system that monitor the conductivity of fuel. A reading greater than 100 ohms or a specific sensor voltage below a predetermined threshold indicates water presence.
What a healthy reading looks like
Sensor should read above 100 ohms resistance or a voltage of at least 0.5V under normal conditions without 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 fuel quality; drain a sample to inspect for water. Decision: if water is present, address contamination; if not, go to step 2.
- 22. Inspect the fuel lines and connections for leaks. Decision: fix any leaks found; if clean, go to step 3.
- 33. Test the water detection sensor for proper resistance (should be below 100 ohms when no water is detected). Decision: if sensor fails, replace it; if it tests good, go to step 4.
- 44. Clear the code and monitor for reoccurrence. Decision: if code reappears, inspect other components and fuel system for further issues.
Common causes
- Fuel contamination with water or ethanol
- Faulty water detection sensor
- Leaking fuel system components
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
No, driving with water in fuel can cause severe engine damage and should be addressed immediately.
Will this code come back after clearing?
Yes, if the underlying issue is not resolved, the code may return.
Why is this code paired with SPN 3064?
SPN 3064 often indicates low fuel pressure which can be a result of water interfering with fuel delivery.
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