OBD-II code · Powertrain (generic)

P04ED EVAP System Large Leak Detected Fresh Air Side

Same as P04EB on the fresh-air side, but with a leak large enough to prevent test build-up. The evaporative system captures fuel vapor from the tank and purges it into intake; leaks or stuck purge valves leak hydrocarbons and cause emissions failures.

Is it safe to drive with P04ED?

Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.

Common causes

  • Most likelyVent valve stuck open
  • PossibleHose pulled off or torn

Symptoms

  • Check engine light on
  • Possible smell of fuel near tank or engine bay
  • Failed emissions inspection
  • Loose-cap warning may appear

Repair at a glance

Difficulty
Easy
DIY friendly
Often, with basic tools
Typical labour
0.4–1.5 h
Emissions test
Likely to fail
Parts involved
Evap Vent Valve, Evap Hose Fresh Air Side

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.