Water in Fuel Condition Detected
Code P1140 indicates that the water-in-fuel sensor has detected excessive water in the diesel fuel system. This typically occurs when water accumulates in the fuel filter/water separator, which can lead to injector damage, poor combustion, and engine performance issues. The sensor triggers the warning to prevent water from reaching the high-pressure fuel system.
01. Most Common Causes
- Water-contaminated fuel from filling station
- Failed fuel filter/water separator
- Condensation in fuel tank
- Damaged or faulty water-in-fuel sensor
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Engine hesitation or rough idle
- Hard starting or stalling
- Reduced fuel economy
03. Step-by-Step Diagnosis
Step 1: Drain water from fuel filter/water separator using the drain valve.
Step 2: Replace fuel filter if water contamination is severe or filter is old.
Step 3: Inspect fuel tank for water accumulation; drain if necessary.
Step 4: Test water-in-fuel sensor for proper operation; replace if faulty.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
No, driving with water in fuel can damage injectors and the fuel pump. Have it serviced immediately.
How much does it cost to fix?▼
Typically $50-$150 for draining and filter replacement; sensor replacement may add $100-$200.