Code result
P04ED
EVAP System Large Leak Detected Fresh Air Side
Moderate severity
What it means
Same as P04EB on the fresh-air side, but with a leak large enough to prevent test build-up. The evaporative system captures fuel vapor from the tank and purges it into intake; leaks or stuck purge valves leak hydrocarbons and cause emissions failures.
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
Vent valve stuck open
highOne of the most commonly reported causes for this code — check this first.
Hose pulled off or torn
mediumA plausible cause — test and verify before replacing parts.
Related help
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