WOMS
P code powertrain Medium severity

P1140 Water In Fuel Condition

The OBD2 code P1140 indicates that the vehicle's engine control module has detected the presence of water in the fuel system, which can affect engine performance and fuel efficiency

Definition

The OBD2 code P1140 indicates that the vehicle's engine control module has detected the presence of water in the fuel system, which can affect engine performance and fuel efficiency

Common causes

  • Contaminated fuel
  • Faulty fuel filter
  • Damaged fuel lines
  • Water ingress from storage or transportation
  • Faulty fuel tank or seals
  • Poor fuel quality
  • Environmental factors (e.g., high humidity)

Common misdiagnoses

  • Fuel Injector Issues
  • Fuel Pump Failure
  • Clogged Fuel Filter
  • Engine Misfire
  • Air Intake Problems
  • Sensor Malfunctions (e.g., MAF or MAP sensors)
  • Fuel Pressure Regulator Issues
  • Contaminated Fuel System
  • ECU/PCM Faults
  • Ignition System Problems

Troubleshooting steps

  1. 1. Check the Fuel Filter

  2. 2. Inspect the fuel filter for signs of water accumulation. Many fuel filters have a water separator that can be drained. If water is present, drain it according to the manufacturer's instructions

  3. 3. Inspect the Fuel System

  4. 4. Look for any signs of leaks or contamination in the fuel lines, tank, and injectors. Ensure that the fuel system is free from any water intrusion

  5. 5. Test the Fuel Quality

  6. 6. If you suspect that water may have entered the fuel system, consider testing the fuel for contamination. You can collect a sample of the fuel and check for water presence using a clear container

  7. 7. Check the Fuel Water Separator

  8. 8. If your vehicle is equipped with a fuel water separator, check it for proper operation. Make sure it is functioning correctly and that it has been drained if necessary

  9. 9. Inspect the Fuel Tank

  10. 10. Examine the fuel tank for any signs of rust or damage that could allow water to enter. If the tank is compromised, it may need to be repaired or replaced

  11. 11. Clear the Code

  12. 12. After addressing any issues, clear the code using an OBD-II scanner and take the vehicle for a test drive to see if the code returns

  13. 13. Monitor for Recurrence

  14. 14. Keep an eye on the vehicle's performance and monitor for any recurrence of the P1140 code. If the code returns, further investigation may be necessary

  15. 15. Check for ECM Updates

  16. 16. In some cases, the ECM may require a software update to address false readings or issues related to water detection. Check with the manufacturer for any available updates

  17. 17. Consult a Professional

  18. 18. If you are unable to resolve the issue or if the code persists after performing the above steps, it may be best to consult a professional mechanic or technician for further diagnosis. By following these troubleshooting steps, you can identify and address the underlying cause of the P1140 code and ensure that your vehicle's fuel system is functioning properly