P0443 – Meaning, Causes, Symptoms, & Fixes

Code P0443 Definition

Evaporative Emission Control System Purge Control Valve Circuit Malfunction

What Does P0443 Mean?

The evaporative control (EVAP) system collects raw fuel escaping from the fuel tank. This information is then communicated to the ECM which regulates the emissions of the vehicle. The P0443 code is set when the ECM detects a malfunction within the purge control valve or a short in the purge valve circuit.

What Are the Symptoms of Code P0443?

*No noticeable adverse conditions in some cases

What Causes Code P0443?

  • Short in control circuit wiring
  • Short in purge valve wiring
  • Faulty vent valve solenoid
  • Faulty purge valve solenoid
  • Faulty ECM

How Serious Is Code P0443?– Low

This trouble code will not prevent your vehicle from operating, but may cause it to fail emissions tests. The most common error(s) include: lowered fuel economy and rough engine performance. It is recommended to have this code fixed to prevent further loss of fuel economy.

Code P0443 Common Diagnosis Mistakes

Prematurely replacing the purge control valve when the issue lies within the wiring or connectors which could have been diagnosed by inspection.

Tools Needed to Diagnose:

  • FIXD

How to Diagnose and Repair:

  1. Check to see if there are any other codes along with P0057 and clear your Check Engine Light with FIXD.
  2. Check the freeze frame data and monitor in an attempt to pinpoint the issue.
  3. Using FIXD, monitor the fuel tank pressure readings to ensure the fuel tank pressure sensor is properly functioning.
  4. The fuel tank pressure sensor provides the primary feedback on engine leaks to the EVAP system of your vehicle.
  5. Verify the fuel cap is not cracked and ensure it is tightly sealed to the vehicle.
  6. Visually inspect the wiring around the purge valve circuit for disconnection.
  7. Confirm the purge control valve and vent valve are properly functioning and holding vacuum for at least half a minute.
  8. If the problem persists, consider replacing the faulty valve.

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Comments 3

Walter Thompson

March 26, 2019

I have an 04 dodge ram with a 5.7 L engine. I’ve replaced the purge valve solenoid, the leak detector valve and the gas cap. My code p0443 still comes up.
The vehicle has 208,000 miles. Any suggestions on what to check next?

Mike

May 3, 2019

Check wiring, follow the wires back and see if they are melted together anywhere. IF you have access to a multimeter test for continuity or voltage and verify it’s as it should be. Check that all hoses are fully seated and not cracked on the side you cannot see. Good luck

Vishal

August 15, 2019

Hi I tried everything test both wires from the purge valve when the ignition is of I got reading from one when it should be both. Also test for continually it was ok from the purge vvalve to the com with a multimeter can you please tell me what to look for thank you

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