P0440 : Evaporative Emission Control System Malfunction

P0440 is the generic OBD-II code for an evaporative emission control system malfunction. It means the ECU detected a fault in the system that captures fuel vapours from the tank and routes them to the engine. The most common trigger is a loose or missing fuel cap, but it can also indicate hose leaks, a failed purge valve, or a cracked charcoal canister.

P0440 est un code defaut lie a systeme evap, classe en gravite low. Lorsque le calculateur de ton vehicule detecte cette condition, il enregistre P0440 et allume le voyant moteur.

Si ton vehicule a declenche P0440, tu peux remarquer un ou plusieurs de ces symptomes :

• Check engine light illuminated
• Faint fuel odour around the vehicle, especially in warm weather
• Possible failed emissions test
• No noticeable driveability issues in most cases
• Fuel cap warning indicator on some vehicles

Voici les causes les plus courantes de P0440, classees selon la probabilite qu'elles soient en cause :

En general oui, pour des trajets courts. P0440 is a generic EVAP fault and does not affect driveability. You can drive normally, but the check engine light will cause an automatic failure at any EU vehicle inspection. Address before your next emissions test.

Suis ces etapes pour identifier la cause profonde de P0440 :

1. Check the fuel cap first. Remove it, inspect the rubber seal for cracks or debris, and re-seat it until it clicks. Clear the code and drive for several cycles to see if it returns
2. Visually inspect EVAP hoses from the fuel tank to the charcoal canister and from the canister to the purge valve at the engine. Look for cracks, brittle plastic, loose clamps, or disconnections
3. Perform a smoke test on the EVAP system. Seal the system, introduce smoke, and watch for visible plumes escaping at hose connections, the canister, or the fuel tank area. Expect 40 to 100 EUR for the diagnostic alone at a workshop
4. Use a scan tool to command the purge valve and vent valve open and closed. Listen for clicking. A stuck-open or stuck-closed valve is a frequent cause
5. If the smoke test reveals no external leaks, inspect the charcoal canister for cracks and check the fuel tank pressure sensor reading with live data

Les couts de reparation de P0440 varient selon la cause profonde et ton vehicule. Voici des estimations courantes :

P0440 se comporte differemment selon ton vehicule. Selectionne ta voiture ci-dessous pour des causes propres au modele, les problemes connus et des estimations de couts ajustees :

Ces codes apparaissent souvent avec P0440 ou indiquent des problemes connexes :