Code result
P0440
Evaporative Emission Control System Malfunction
Moderate severity
What it means
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.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Fuel filler cap loose or worn
highOne of the most commonly reported causes for this code — check this first.
Purge valve stuck open or closed
mediumA plausible cause — test and verify before replacing parts.
Cracked EVAP hose
mediumA plausible cause — test and verify before replacing parts.
Related help
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