Water In Fuel Indicator Circuit Malfunction
Your vehicle's water detection system in the fuel tank isn't working properly, like a smoke detector with a dead battery. The ECU can't reliably sense if water has contaminated your fuel supply.
The ECU monitors a capacitive water-in-fuel sensor in the fuel tank that detects changes in electrical conductivity when water is present. The sensor sends a voltage signal to the ECM, which compares it against calibrated thresholds to determine if water contamination exists.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Sensor voltage signal | 0.5–4.5V (dry fuel) | Below 0.2V or open circuit (water detected or sensor failure) |
| Signal response time | <500ms transition | No change or delayed response (wiring/sensor malfunction) |
Code P1144 is a moderate fault. You can generally drive to a workshop, but avoid long trips or high-load driving (motorway, uphill towing) until it is diagnosed. If the code keeps returning after clearing, or if you notice the symptoms listed above worsening, do not delay professional diagnosis. Many moderate codes have multiple possible root causes — a mechanic with live OBD data can identify the exact fault more efficiently than part-by-part trial and error.
Once the fault is repaired, P1144 can be cleared using any OBD-II scanner. Connect the scanner, navigate to "Clear Codes" or "Erase DTCs," and confirm. The check engine light turns off immediately.
The code will return if the root cause was not actually fixed. The ECM re-detects the fault within 1–3 drive cycles and sets the code again.