OBD-II code · Powertrain (generic)

P04EA EVAP System Small Leak Detected Fuel Tank Side

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.

Is it safe to drive with P04EA?

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

Common causes

  • Most likelyFuel cap not sealing properly
  • PossibleVapor hose porous or cracked

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
0.3–2 h
Emissions test
Likely to fail
Parts involved
Fuel Tank, Fuel Cap, Fuel Sender Seal, Evap Hose Tank Side

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