P04EA

EVAP System Small Leak Detected Fuel Tank Side

Moderate severity

The EVAP leak diagnostic has detected a small leak on the fuel tank side of the system - typically a hose, gasket, fuel cap, or fuel sender flange that does not seal completely. Vapor escapes during pressure or vacuum tests.

Common causes

Fuel cap not sealing properly
One of the most commonly reported causes for this code — check this first.
high
Typical part cost: $30-390
Vapor hose porous or cracked
A plausible cause — test and verify before replacing parts.
medium
Typical part cost: $30-390
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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

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Frequently asked questions

What does P04EA mean?

P04EA means "EVAP System Small 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 P04EA?

fuel cap not sealing properly; vapor hose porous or cracked — 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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