The evaporative emission control (EVAP) system is designed to prevent fuel vapors from escaping into the atmosphere. The EVAP system includes a purge control valve that opens and closes to allow fuel vapors to be purged from the charcoal canister into the engine.
When the engine is running, the PCM opens the purge control valve to allow fuel vapors to be purged from the charcoal canister into the engine. When the engine is turned off, the PCM closes the purge control valve to prevent fuel vapors from escaping into the atmosphere.
If the PCM detects a problem with the EVAP system, it will set a diagnostic trouble code (DTC). DTC P0443 is set when the PCM detects that the purge control valve circuit is open or shorted.
Possible causes of DTC P0443 include:
- Faulty purge control valve
- Open or shorted wiring in the purge control valve circuit
- Faulty PCM
Symptoms of DTC P0443 may include:
- Check Engine Light on
- Rough idling
- Stalling
- Poor fuel economy
How to diagnose DTC P0443
1. Check the wiring in the purge control valve circuit for any open or shorted wires.
2. Test the purge control valve to see if it is functioning properly.
3. If the purge control valve and wiring are functioning properly, the PCM may be faulty.
How to fix DTC P0443
1. Replace the faulty purge control valve.
2. Repair any open or shorted wires in the purge control valve circuit.
3. Replace the faulty PCM.
Conclusion
DTC P0443 is a diagnostic trouble code that indicates a problem with the EVAP system purge control valve circuit. This code can be caused by a faulty purge control valve, open or shorted wiring in the purge control valve circuit, or a faulty PCM.
