Error code P0444 is displayed and the check engine light is on - what does this mean?
The OBD/EOBD system has detected a fault in the evaporative emission control system, specifically an open circuit in the carbon canister purge valve. This DTC P0444 affects the EVAP system, which prevents fuel vapors from being released into the atmosphere. This fault code may show slight variations in the diagnosis for different manufacturers.
What can cause this fault code?
- Defective EVAP purge valve (purge valve)
- Damaged cable connections to the purge valve
- Loose or corroded plug connections
- Interrupted power supply to the valve
- Defective motor control (ECM/PCM)
- Damaged vacuum hoses in the EVAP system
- Blown fuse in the EVAP circuit
What symptoms occur in parallel with fault code P0444?
- Check engine light: Permanent activation of the check engine light
- Fuel smell: Perceptible gasoline vapors around the vehicle
- Starting problems: Occasional difficulties starting the engine
- Unsteady idling: Engine runs irregularly at idle speed
- Increased emissions: Deteriorated exhaust emission values at the main inspection
- Fuel consumption: Slightly increased consumption due to inefficient vapor recovery
How can the problem with error code P0444 be rectified?
- Repairing trouble code P0444 requires systematic diagnosis and targeted measures.
- Replace the EVAP flush valve: Replace defective valve with original part and check electrical connections
- Repair wiring harness: Locate damaged cables, repair severed wires or replace complete wiring harness
- Clean plug connections: Remove corrosion from plugs, treat contacts with contact spray and connect firmly
- Check fuses: Identify blown fuse in EVAP circuit and replace with correct amperage rating
- Replace vacuum hoses: Replace cracked or porous hoses in the evaporation system with new original parts
- Engine control unit diagnosis: Check ECM/PCM with professional diagnostic software and replace or repair if defective
FAQ - Frequently asked questions about DTC P0444
Can I continue driving with error code P0444?
Yes, the vehicle basically remains roadworthy, but you should have the fault code rectified as soon as possible. The EVAP system does not directly affect driving safety, but increased emissions can lead to problems during the main inspection.
How much does it cost to repair fault code P0444?
The repair costs vary between 80-350 euros. A new EVAP purge valve costs around 50-120 euros, while labor and diagnostics add another 30-80 euros. For more complex wiring harness problems, the costs can reach up to 500 euros.
How long does it take to repair code P0444?
Most repairs take 1-3 hours. Replacing the purge valve takes around 30-60 minutes, while diagnosing wiring problems can take additional time. More complex repairs to the wiring harness can take half a working day.
Can P0444 disappear by itself?
No, this eobd fault code does not disappear spontaneously. The problem in the EVAP system requires physical repair of the defective components. Even after temporarily deleting the code, P0444 will return as long as the root cause has not been resolved.
What tools do I need for P0444 diagnostics?
You need an OBD2 scanner, a digital multimeter and basic tools. For professional diagnostics, a vacuum pump, oscilloscope and manufacturer-specific diagnostic software are recommended. Most hobby mechanics should limit themselves to simple visual inspections.
Is P0444 a serious fault?
Error code P0444 is considered moderate. While there is no immediate danger to the engine or driver, untreated EVAP problems can lead to increased emissions and possible consequential damage. Prompt repair is therefore recommended.