P code powertrain Medium severity

P0313 Misfire Detected with Low Fuel

The OBD2 code P0313 indicates that the engine control module has detected a misfire condition while the fuel level is low, which may affect engine performance and emissions

Definition

The OBD2 code P0313 indicates that the engine control module has detected a misfire condition while the fuel level is low, which may affect engine performance and emissions

Common causes

  • Low fuel level
  • Fuel pump failure
  • Clogged fuel filter
  • Faulty fuel injectors
  • Vacuum leaks
  • Ignition system issues (spark plugs, ignition coils)
  • Engine mechanical problems (worn piston rings, valves)
  • Faulty mass air flow sensor (MAF)
  • Faulty engine control module (ECM)

Common misdiagnoses

  • Fuel pump failure
  • Fuel filter blockage
  • Ignition coil issues
  • Spark plug problems
  • Vacuum leaks
  • Engine timing issues
  • Mass air flow sensor malfunction
  • EGR valve problems
  • Injector issues
  • Engine compression problems

Troubleshooting steps

  1. 1. Check Fuel Level

  2. 2. Ensure that the fuel tank has an adequate amount of fuel. Low fuel levels can cause misfires due to insufficient fuel delivery

  3. 3. Inspect Fuel System

  4. 4. Fuel Pump

    Check if the fuel pump is functioning properly. Listen for the pump's operation when the ignition is turned on

  5. 5. Fuel Filter

    Inspect the fuel filter for clogs or restrictions that could impede fuel flow

  6. 6. Fuel Injectors

    Check for clogged or malfunctioning fuel injectors. Cleaning or replacing them may be necessary

  7. 7. Examine Ignition System

  8. 8. Spark Plugs

    Inspect the spark plugs for wear, fouling, or damage. Replace them if necessary

  9. 9. Ignition Coils

    Test the ignition coils to ensure they are providing adequate spark. Replace any faulty coils

  10. 10. Wiring and Connectors

    Check the wiring and connectors related to the ignition system for damage or corrosion

  11. 11. Check for Vacuum Leaks

  12. 12. Inspect the intake manifold and vacuum hoses for leaks that could lead to a lean air-fuel mixture, causing misfires

  13. 13. Examine Engine Sensors

  14. 14. Mass Air Flow (MAF) Sensor

    Ensure the MAF sensor is clean and functioning correctly, as it plays a crucial role in determining the correct air-fuel mixture

  15. 15. Throttle Position Sensor (TPS)

    Check the TPS for proper operation, as it affects engine performance

  16. 16. Oxygen Sensors

    Inspect the oxygen sensors for proper operation, as they help regulate the air-fuel mixture

  17. 17. Check Engine Compression

  18. 18. Perform a compression test to ensure that the engine has adequate compression in all cylinders. Low compression can lead to misfires

  19. 19. Scan for Additional Codes

  20. 20. Use an OBD-II scanner to check for any other trouble codes that may provide additional insight into the issue

  21. 21. Inspect Engine Timing

  22. 22. Check the timing belt or chain to ensure it is properly aligned and functioning. Incorrect timing can lead to misfires

  23. 23. Review Recent Repairs or Changes

  24. 24. If any recent repairs or changes were made to the vehicle, review them to see if they could be related to the misfire issue

  25. 25. Test Drive and Monitor

  26. 26. After performing the necessary repairs or adjustments, take the vehicle for a test drive to see if the code returns and monitor engine performance. If the issue persists after following these steps, it may be advisable to consult a professional mechanic for further diagnosis and repair