Powertrain
generic / SAE
P0440
Evaporative Emission Control System Malfunction
A general fault in the evaporative emission (EVAP) system has been detected. The system seals the fuel tank and captures fuel vapour in a charcoal canister; this code indicates a failed leak test or sensor without identifying the specific failure.
SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number4 / 40
Possible causes
- Fuel filler cap loose or worn high
- Purge valve stuck open or closed medium
- Cracked EVAP hose medium
Symptoms
- Check engine light on
- Possible smell of fuel near tank or engine bay
- Failed emissions inspection
- Loose-cap warning may appear
Inspection / repair
- Difficulty: easy
- DIY: possible
- Estimated cost: 20–350 €
- Estimated time: 0.2–2.5 h
- Component: evap canister
- Component: evap purge valve
- Component: fuel filler cap
- Component: evap vent valve
- MIL / check engine light
- emissions-relevant
- drive cycle required
Sources
References
sae:J2012