WOMS
P code powertrain Medium severity

P043E Evaporative Emission System Leak Detection Reference Orifice Low Flow

The OBD2 code P043E indicates that the evaporative emission system is detecting a low flow condition in the reference orifice used for leak detection, suggesting a potential issue with the system's ability to identify...

Definition

The OBD2 code P043E indicates that the evaporative emission system is detecting a low flow condition in the reference orifice used for leak detection, suggesting a potential issue with the system's ability to identify leaks

Common causes

  • Clogged or damaged evaporative emission canister
  • Faulty or damaged purge valve
  • Leaking or damaged vacuum lines
  • Faulty fuel tank pressure sensor
  • Blocked or damaged vent valve
  • Low fuel level
  • Faulty or damaged fuel cap
  • Electrical issues or poor connections in the EVAP system

Common misdiagnoses

  • Faulty EVAP canister
  • Leaking fuel cap
  • Damaged or cracked EVAP hoses
  • Faulty purge valve
  • Faulty vent valve
  • Clogged charcoal canister
  • Faulty fuel tank pressure sensor
  • Wiring issues or connector problems
  • PCM (Powertrain Control Module) issues
  • Incorrectly installed or damaged fuel tank

Troubleshooting steps

  1. 1. Visual Inspection

    Check for Leaks: Inspect the EVAP system components, including hoses, connectors, and the fuel tank, for any visible signs of leaks or damage

  2. 2. Inspect the Orifice

    Locate the reference orifice and check for blockages or damage

  3. 3. Check the Gas Cap

    Ensure Proper Sealing: Make sure the gas cap is properly tightened and seals correctly. A loose or damaged gas cap can cause EVAP system issues

  4. 4. Replace if Necessary

    If the gas cap is cracked or damaged, replace it

  5. 5. Test the EVAP System

    Smoke Test: Perform a smoke test to identify any leaks in the EVAP system. This involves introducing smoke into the system and looking for escaping smoke

  6. 6. Pressure Test

    Check the system for proper pressure. A pressure gauge can help determine if the system is holding pressure as it should

  7. 7. Inspect the Purge and Vent Valves

    Check Operation: Ensure that the purge valve and vent valve are functioning correctly. They should open and close as needed during the EVAP system operation

  8. 8. Electrical Connections

    Inspect the electrical connections to these valves for corrosion or damage

  9. 9. Check the Reference Orifice

    Clean or Replace: If the reference orifice is clogged or damaged, clean or replace it as necessary

  10. 10. Verify Specifications

    Ensure that the orifice is the correct size and type for your vehicle

  11. 11. Scan for Additional Codes

    Check for Related Codes: Use an OBD-II scanner to check for any other related trouble codes that may provide additional context for the issue

  12. 12. Inspect the Fuel Tank and Lines

    Check for Damage: Inspect the fuel tank and associated lines for any signs of damage or wear that could lead to leaks

  13. 13. Look for Cracks

    Pay special attention to the area around the fuel filler neck and any connections

  14. 14. Check the PCM (Powertrain Control Module)

    Software Updates: Ensure that the PCM has the latest software updates, as manufacturers may release updates to address known issues

  15. 15. Reprogram or Replace

    If the PCM is suspected to be faulty, consider reprogramming or replacing it

  16. 16. Clear Codes and Test Drive

    Reset the Codes: After performing repairs, clear the trouble codes and take the vehicle for a test drive to see if the code returns

  17. 17. Monitor for Recurrence

    Keep an eye on the vehicle's performance and monitor for any reoccurrence of the P043E code

  18. 18. Consult a Professional

    If the issue persists after performing these steps, it may be best to consult a professional mechanic or technician who has experience with EVAP system diagnostics. By following these troubleshooting steps, you should be able to identify and resolve the issue related to the P043E code