Code result
P04EF
EVAP System Very Small Leak Detected Fresh Air Side
Moderate severity
What it means
Same as P04EE on the fresh-air side - microcrack in a hose or imperfect vent valve seal at the most sensitive test threshold.
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 seal aged
highOne of the most commonly reported causes for this code — check this first.
Related help
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