OBD-II code · Powertrain (generic)

P04EB EVAP System Small Leak Detected Fresh Air Side

Same as P04EA but on the fresh-air side - the path between vent valve and atmosphere is not sealing completely during the active test phase.

Is it safe to drive with P04EB?

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

Common causes

  • Most likelyVent valve does not seal in test mode
  • PossibleHose 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
0.5–2 h
Emissions test
Likely to fail
Parts involved
Evap Vent Valve, Evap Canister, Evap Hose Fresh Air Side

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