Detailed Description of Error P043E
OBDII error code P043E indicates that the Evaporative Emission (EVAP) leak detection reference orifice has low flow. The EVAP system is responsible for capturing and re-circulating fuel vapors from the fuel tank and engine. The reference orifice is a critical component of the EVAP system, as it provides a calibrated flow restriction that helps the system detect leaks.
The reference orifice is typically a small, precisely drilled hole that creates a specific flow restriction in the EVAP system. When the engine computer (PCM) detects that the flow through the reference orifice is lower than expected, it sets code P043E. This code indicates that the EVAP system is not functioning properly, and that there may be a leak or blockage in the system.
Possible Causes of Error P043E
- Clogged or restricted reference orifice
- Leak or blockage in the EVAP system, including hoses, connections, or components
- Failed or faulty EVAP canister purge valve
- Failed or faulty EVAP vent valve
- EVAP system plumbing or routing issues
- Faulty or damaged EVAP system sensors or wiring
- PCM or module malfunction
Possible Fixes for Error P043E
- Inspect the EVAP system for leaks or blockages, and repair or replace components as needed
- Clean or replace the reference orifice if it is clogged or restricted
- Check and replace the EVAP canister purge valve and vent valve if faulty
- Verify proper EVAP system plumbing and routing, and make corrections as needed
- Check and repair or replace EVAP system sensors and wiring if damaged
- Use a scan tool to monitor EVAP system operation and identify the root cause of the problem
- If all else fails, consider replacing the PCM or module if it is malfunctioning