Skip the auto shop - Our mechanics make house calls

P0443 OBD-II Trouble Code: Evaporative Emission Control System Purge Control Valve Circuit Malfunction

check engine light logo

P0443 code definition

Evaporative Emission Control System Purge Control Valve Circuit Malfunction

What the P0443 code means

P0443 is an OBD-II generic code that the engine control module (ECM) has detected a malfunction with the purge control valve or its control circuit. This could mean an open or short in the valve or circuit.

What causes the P0443 code?

  • The ECM has commanded the purge control valve to open and detected either an incomplete open circuit or a short in the circuit.

  • The cause of code P0443 can be a purge control valve internal open circuit or the connector is corroded causing loss of contact with the valve.

  • The code can also be set if the wiring to the valve is damaged between the ECM and the purge valve causing an open circuit if the wire is cut or a short if the wire is shorted to ground or a power source.

What are the symptoms of the P0443 code?

  • The Check Engine Light will be illuminated and the code is set in ECM memory.

  • You may notice a slight drop in fuel mileage if the vapor system is not working.

How does a mechanic diagnose the P0443 code?

  • Scans codes and documents the code in the ECM, views the freeze frame data see when the fault happened

  • Inspects the entire vapor purge valve wiring and system to include the purge valve connector for corrosion, damaged or loose connection or wires

  • Checks the purge valve vent for any blockage from dirt, debris, or spider webs

  • Performs a smoke leakage test on the fuel vapor system to try and locate the cause of the vapor leak using the test vapor port

  • Checks the purge control valve for proper resistance of valve and then check operation of valve using the ECM to control the valve

Common mistakes when diagnosing the P0443 code

  • Not checking and assuming the purge control valve is defective without doing a thorough diagnostics of the complete system to later find the wiring is broken or cut

  • Not verifying the failure and replacing parts that may or may not be the problem

How serious is the P0443 code?

  • Code P0443 causes the check engine light to go on and this alone will cause a failed emission test.

  • The code means the fuel vapor system control valve is defective or the circuit to it is not making the connection to the valve so the ECM lost control to the valve.

  • The vapor recovery and reuse system if not working correctly can cause a loss of fuel mileage.

What repairs can fix the P0443 code?

  • Testing and replacing the purge control valve
  • Repairing the damaged wiring to the purge control valve and secure from getting damaged again
  • Replacing the purge vent valve

Additional comments for consideration regarding the P0443 code

Code P0443 is a pretty common code that vehicles come in with today that causes the check engine light to come on. The most common cause is the fuel cap was accidently left off or not tightened securely after getting fuel. For this code the most common failure is the purge control valve has an internal open circuit or the vent valve will not hold in the vapors.

Need help with a P0443 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P0222 OBD-II Trouble Code: Throttle/Pedal Position Switch/Sensor B Circuit Low Input
P0222 code definition Throttle/Pedal Position Switch/Sensor B Circuit Low Input What the P0222...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...


Related questions

Q: rough idle, heavy missing, fault codes P0301 and P0456. lack of power, where do i start to diagnose this?

Hi there. From the description you have provided, for the P0301 rough idle and heavy misfire and P0456 evaporative small leak detected, the problems are unrelated. The P0301 is a #1 cylinder misfire code. It could be, a spark plug...

Q: Check engine light on.

The P0125 code does not necessarily mean you have a bad sensor, What it indicates is that the signal from the sensor is telling the computer that the engine is not warming up. That could be a sensor, or it...

Q: The truck is riding hard

When you say the truck is riding hard, I have seen many of the suspension struts binding causing a hard ride. They do not shift to smooth ride and may stay stiff. Replacing the shock/struts fixed the issue with ride....