P04EC
EVAP System Large Leak Detected Fuel Tank Side
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.
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.
Common causes
- high
Fuel cap missing or not seated
One of the most commonly reported causes for this code — check this first.
Typical part cost: $30-330
- medium
Vapor hose pulled off or torn
A plausible cause — test and verify before replacing parts.
Typical part cost: $30-330
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
See related trouble codes
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Frequently asked questions
What does P04EC mean?
P04EC means "EVAP System Large Leak Detected Fuel Tank Side". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P04EC?
fuel cap missing or not seated; vapor hose pulled off or torn — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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