I'm seeking help troubleshooting a PO443 fault code on my 1997 Ford Taurus. I've already replaced the purge control valve, but the issue persists. Could the fuel cap be the root cause? Any guidance on further diagnostic steps would be greatly appreciated.
I found a relevant article describing a similar issue on my vehicle. The resolution involved replacing the vehicle's engine control module (ECM). Given the symptom similarity and the presence of an electrical circuit failure code related to the torque converter solenoid, I'm leaning toward a similar conclusion here. I tested the solenoid and its wiring directly at the plug-in connector, and everything functions correctly. The solenoid can be energized and operates properly. Using a diagnostic scanner, I confirmed that no circuit failure is detected—yet the code persists. Thank you for your response. rm
It seems the PO443 code may be invalid or misleading. The vehicle's engine control unit (ECM) might have an internal malfunction. Despite this, the transmission shifts smoothly and operates normally. Based on the evaporation system diagnostic data, I conclude that the issue is likely originating within the ECM itself. While I'm considering a replacement, it won't happen in the near future. rm
Ensure that all wiring and the electrical circuit are intact. Check the connector for proper seating and verify that the pins inside the connector are not bent or spread apart.