P04EC fault code: what it means

P04EC: EVAP large leak, fuel tank side. On 2021 JL Wrangler (incl. 4xe) FCA replaced the upper filler tube and cap; 'Check Gas Cap' message often shows.

Engine and gearbox (powertrain) · Minor

Usual causes, most likely first

1. leaking fuel filler cap/neck seal
2. loose cap
3. tank-side EVAP hose

P04EC by make

Not sure what P04EC means on your car? Ask Credov.

Before you clear it

Write the code down or photograph the scanner first. A code that comes straight back after clearing points to a fault that is still there. A car whose codes were cleared just before you arrived may be hiding one: the scanner's readiness monitors show "not ready" for a while after codes are cleared.

Researched by Credov from manufacturer and workshop sources. A fault code points to where a fault may be; a workshop confirms it with a diagnosis. Browse all fault codes.