Broken, corroded, or disconnected wire in the purge valve control circuit; Failed purge valve solenoid with an open internal coil; Blown fuse or faulty relay supplying power to the purge valve; Corroded or loose electrical connector at the purge valve; Damaged engine computer driver circuit (rare); Rodent damage to wiring harness

DTC codes / P04xx · Auxiliary emission controls / P0444

P0444EVAP Purge Control Valve Circuit Open

Q: What does code P0444 mean?

EVAP Purge Control Valve Circuit Open. P0444 means the engine computer has detected an open circuit on the electrical path that controls the EVAP purge valve, so it cannot command the valve to open and pull fuel vapor into the intake. The computer monitors the purge valve control circuit and sets this code when the voltage on the control wire does not behave as expected, indicating a break in the circuit rather than a mechanical valve failure.

P0444 means the engine computer has detected an open circuit on the electrical path that controls the EVAP purge valve, so it cannot command the valve to open and pull fuel vapor into the intake. The computer monitors the purge valve control circuit and sets this code when the voltage on the control wire does not behave as expected, indicating a break in the circuit rather than a mechanical valve failure.

SystemPowertrain

Code typeGeneric (all makes)

SeverityLow

Fix difficultyIntermediate

AreaAuxiliary emission controls

Symptoms you may notice

Illuminated check engine light, often with no other symptoms
A faint fuel odor may be present if the valve is stuck open or the system is compromised
Rough idle or stalling in rare cases if the valve is stuck open and allows unmetered vapor into the intake
Slightly increased fuel consumption or emissions over time
Failed emissions test due to the check engine light being on
No noticeable performance change in most cases

Common causes, most likely first

Broken, corroded, or disconnected wire in the purge valve control circuit
Failed purge valve solenoid with an open internal coil
Blown fuse or faulty relay supplying power to the purge valve
Corroded or loose electrical connector at the purge valve
Damaged engine computer driver circuit (rare)
Rodent damage to wiring harness

How to diagnose and fix it

Inspect the purge valve connector and wiring for obvious damage, corrosion, or disconnection
Check the fuse and relay that supply power to the purge valve circuit
Measure resistance across the purge valve solenoid terminals and compare to specification
Test for power and ground at the purge valve connector with the key on and engine off
Check continuity of the control wire from the purge valve to the engine computer
Replace the purge valve if the coil is open or the valve fails a functional test
Repair or replace damaged wiring and clear the code, then verify the repair with a scan tool

What a purge valve open circuit really means

An open circuit code does not always mean the valve itself has failed; a simple unplugged connector or a broken wire is just as likely and far cheaper to fix.
Many technicians replace the purge valve only to find the code returns because the real problem is a corroded terminal or a rubbed-through wire hidden inside the harness loom.
A stuck-open purge valve can cause a rough idle or stalling, but an open circuit usually means the valve cannot open at all, so driveability symptoms are often absent.
The engine computer may set P0444 as a pending code before the check engine light comes on, so a scan tool that reads pending codes can catch the fault early.
Always check for related EVAP codes such as P0443 or P0455 before condemning the purge valve, because multiple codes can point to a shared wiring or connector issue.

Can I keep driving with P0444?

The vehicle is safe to drive with P0444 because the purge valve is not a safety-critical component, but the check engine light will stay on and the vehicle will fail an emissions inspection. Avoid ignoring the light for long periods, as a stuck-open valve could eventually cause driveability issues or increased emissions.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.