Code result
P04EC
EVAP System Large Leak Detected Fuel Tank Side
Moderate severity
What it means
Same as P04EA but the leak is large enough that the system cannot build the test pressure or vacuum at all - typically a missing fuel cap, an unseated hose or a torn vapor line on the tank side.
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 cap missing or not seated
highOne of the most commonly reported causes for this code — check this first.
Vapor hose pulled off or torn
mediumA plausible cause — test and verify before replacing parts.
Related help
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