P043E - EVAPORATIVE EMISSION SYSTEM LEAK DETECTION EVAPORATIVE EMISSION SYSTEM LEAK DETECTION LOW FLOW REFERENCE ORIFICE

The Evaporative Emission Control System, known as the EVAP System, is designed to store fuel vapors to prevent them from escaping into the atmosphere. This system has a ventilated tank that stores these vapors until it is possible to burn them completely under the appropriate conditions.

There are EVAP systems that have an electronic leak detector pump that generates pressure within the system, allowing the flow or leak detection to be checked. The leak detection reference orifices may be at one or more points in the system and are generally in-line, thus measuring an accurate degree of flow with the pump active. The PCM employs the input signal from the sensors and the reference orifices to detect if the leak detection system is operating correctly.

When the DTC P043E OBDII code is stored, it is because the PCM detected discrepancies in the EVAP leak detection reference orifice due to a low flow condition.

• Check Engine light on.
• Slight increase in fuel consumption.

The reasons for setting the P043E OBD2 diagnostic code are:

• A leak detection port may have blockages.
• EVAP vacuum lines could be damaged.
• The carbon element could have deficiencies.
• Purge Control Solenoid or EVAP Pressure Sensor may be defective.
• Leak Detection Pump may have damage.

To troubleshoot the P043E OBDII fault code consider the following:

• Consult the TSBs.
• Check if the DTC P043E is stored along with other codes related to the Evaporative Emission Control System. If so, diagnose them according to the order obtained.
• Verify that the EVAP leak detection orifice(s) and vacuum lines are not deficient due to blockage or other damage. Correct as applicable.
• Checks the condition of the carbon element and other components of the EVAP System. To do this, follow the manufacturer's guide in their specifications. Make adjustments as necessary.