P043F - EVAPORATIVE EMISSION SYSTEM LEAK DETECTION EVAPORATIVE EMISSION SYSTEM LEAK DETECTION REFERENCE ORIFICE HIGH FLOW

The EVAP is a system designed to store fuel vapors in order to prevent them from escaping into the atmosphere. The EVAP has a vented canister or tank that stores these vapors, until such time as they can be completely burned under the proper conditions.

Some EVAP systems include an electronic pump that detects leaks and generates pressure within the system so that flow or leak detection can be verified. Leak detection reference orifices are also included in the system and are usually in-line to ensure an accurate flow rate reading with the pump running. The PCM uses the input signal from the system sensors and the reference from these orifices to calculate if the leak detection performance is adequate.

When set the P043F OBDII fault code is due to, the detection of inconsistencies in the EVAP leak detection reference orifice caused by excessively high flow.

• Check Engine lamp illuminates.
• A slight increase in fuel consumption is noticed.

The storage of the DTC P043F OBD2 occurs because of the following:

• A leak detection port could be blocked.
• EVAP could have vacuum lines in poor condition.
• Possibly the carbon element is in bad condition.
• The EVAP Pressure Sensor or Purge Control Solenoid could be deficient.
• The Leak Detection Pump may be damaged.

In order to troubleshoot the P043F OBDII diagnostic code consider the following:

• Consult the Technical Service Bulletins.
• Using a scanner, check if in addition to code P043F there are other EVAP System-related DTCs Diagnose them in the order shown.
• Inspect the EVAP leak detection ports and vacuum lines for blockages or other deficiencies. Repair it as applicable.
• Verify the integrity of the carbon element, Leak Detection Pump, and other EVAP This diagnosis should be performed following the manufacturer's recommendations. Correct it as required.