Emissions control: EGR, DPF, catalytic converter and AdBlueGeneric OBD-II codeUrgency: Monitor
Code P0444: EVAP: purge valve circuit open
What code P0444 means
The ECU has detected an open circuit in the EVAP system purge valve: there is no electrical continuity between the ECU and the valve, or inside it.[1][2]
That valve lets the petrol vapours stored in the charcoal canister pass into the intake; if the circuit is open, it cannot be commanded and purging stops.[2][3]
It is a generic code, related to P0443 and P0445 (shorted circuit).[1]
Original definition (SAE J2012): Evaporative Emission System Purge Control Valve Circuit Open[1]
Causes of P0444
From most to least likely, according to the sources.
- 1Purge valve with an open internal coil.[2]
- 2Valve connector disconnected, or a broken control wire between the valve and the ECU.[2]
- 3Blown fuse in the valve's supply or corroded wiring ground.[2]
- 4Damaged EVAP system wiring or connectors, or leaks in the system.[3]
- 5ECU fault, according to one source.[3]
Symptoms
- Engine warning light on; the engine usually runs normally.[2]Engine warning light: faults that cause it
- Smell of petrol if purging stops completely and vapours build up in the charcoal canister.[2]Fuel smell: faults that cause it
- Uneven idle according to CarWiki, which also cites loss of power and erratic consumption.[3]Vibrations: faults that cause it
How to diagnose P0444
In order: from the most likely and cheapest to check to the most expensive.
- 1Check that the purge valve connector is properly seated.[2]
- 2Measure the coil's resistance: Carista gives 20 to 30 ohms as a typical value and infinite resistance if it is open. Look up the figure for your model.[2]
- 3Check that power reaches the valve when the ECU calls for it and check the fuse and the ground.[2]
- 4Inspect the EVAP wiring and connectors for breaks or corrosion.[2][3]
- 5Replace the valve or repair the wiring, and clear the codes after each repair to see whether they come back.[2][3]
Can I keep driving with P0444?
Monitor
The sources differ: Carista says the engine usually runs normally and the only risk is failing the emissions test; CarWiki says you can carry on but advises against it because of higher emissions and consumption. It should be repaired soon.[2][3]
Documented faults related to P0444
Known faults of specific engines and cars, with their repair cost, the affected years and their sources.
Wiring, connectors and short circuits: the most serious faults by engine and car
- Critical severityFrequency: OccasionalBMW N62 / N63Additional turbo coolant pump with a risk of short circuit and fireIn 2011 BMW recalled 5, 6 and 7 Series, X5 and X6 models built between 2007 and 2011 because of the additional turbo coolant pump: moisture, a short circuit and, in extreme cases, a fire. In 2012 there was another campaign for a crack in the pump, with a more robust version.
- High severityFrequency: Occasional1.3 TCeBlown fuel pump fuseOn the Renault Captur II and Clio V with the 1.3 TCe engine, a 20-amp fuse can blow and leave the car without an engine. According to L'argus, in April 2021 this fault still had no factory fix; the official service centre's diagnosis includes checking, and sometimes replacing, the catalytic converter.
- High severityFrequency: OccasionalM264/M254Poorly tightened 48 V earth wiring in the mild-hybrid system (fire risk)Mercedes-Benz has issued several recalls (2022-2025) because the 12 V and 48 V earth connections of some cars with a 48 V system may be poorly tightened: resistance rises, the connection heats up and a fire cannot be ruled out. The official workshop checks them and repairs them if necessary in an hour or more.
- High severityFrequency: Occasional1.9 TDIUnit injector tappet wear and injector wiring damageOn the unit injector system, the tappets that operate the injectors can wear if the oil is not changed on time, and the injector wiring can be damaged by contact with oil, causing misfires or loss of power.
- Critical severityFrequency: CommonRover 75Seat SRS connector fault with airbag and seatbelt warning light onAuto Express warns that the Rover 75's seat SRS connector can cause the airbags to fail, and dealers were fixing it with revised connectors. The Dutch APK inspection puts the airbag or seatbelt fault warning among the most frequent defects across almost all series.
- Critical severityFrequency: OccasionalAlfa Romeo GiuliettaShort circuit from badly routed wiring that can prevent gear shifting (KBA campaign, 2010-2015)Yes: according to Germany's KBA, on Alfa Romeo Giulietta cars built between 2010 and 2015 inadequate cable routing could cause a short circuit and, as a result, gear-shift failure.
Frequently asked questions
Can I drive with code P0444?
Yes, according to the sources you can, although CarWiki advises against it for long journeys because of the emissions and consumption. The warning light and possible lack of purging are usually all there is.[2][3]
What is the difference from P0443?
P0443 is a generic fault in the purge valve circuit; P0444 specifically indicates that the circuit is open.[1]
How much does it cost to fix?
Carista estimates between £80 and £300 and CarWiki between €75 and €400. These are generic estimates.[2][3]
Will I pass the MOT with code P0444?
If the code has switched on the engine warning light, no: with that light on, the inspection records a serious defect, and on Euro 5 and Euro 6 cars the ITV (Spain's roadworthiness inspection, similar to the MOT) also reads the OBD diagnostic system. Repair the fault before you go; clearing the code just before the inspection does not help either, because it counts as a serious defect.[4]
Not sure what is wrong with your car? Describe what you notice in the symptom diagnosis or see all fault codes.
Sources
Every fact on this page links to its source. If you find an error, let us know.
- P0444 – AutoDTCsAutoDTCs · Technical documentation · consulted 29 October 2026
- P0444: OBD2 diagnostic trouble codeCarista · Technical documentation · consulted 29 October 2026
- OBD Fehlercode P0444CarWiki.de · Technical documentation · consulted 29 October 2026 · in German
- Desmontando mitos: ¿puede pasar mi coche la ITV con el testigo de «avería motor» encendido?Diariomotor · Motoring press · published 8 March 2021 · consulted 2 October 2026 · in Spanish