EVAP Purge Control Valve Circuit Open
The P0444 code indicates that the Powertrain Control Module (PCM) has detected an open circuit in the Evaporative Emission (EVAP) purge control valve solenoid. This valve regulates the flow of fuel vapors from the charcoal canister to the intake manifold. An open circuit means there is a break in the electrical path, preventing the solenoid from operating. Common causes include a faulty purge valve, damaged wiring, or a poor electrical connection.
1. Most Common Causes
- Faulty EVAP purge control valve
- Open or shorted wiring in the purge valve circuit
- Corroded or loose electrical connector at the purge valve
- Failed PCM (rare)
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Possible fuel odor
- Rough idle or hesitation
- Failed emissions test
3. Step-by-Step Diagnosis
Step 1: Use an OBD2 scanner to confirm P0444 and check for other codes.
Step 2: Visually inspect the purge valve connector and wiring for damage or corrosion.
Step 3: Test the purge valve solenoid resistance with a multimeter (typically 20-30 ohms).
Step 4: Check for 12V power and ground at the connector with the engine running.
Step 5: If wiring and power are good, replace the purge valve.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
Yes, but it may cause rough idle and increased emissions. It's best to repair soon to avoid failing an emissions test.
How much does it cost to fix?▼
Typically $50-$150 for parts and labor, depending on the vehicle and shop rates.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.