All trouble codes → EVAP (evaporative emissions) leak codes
EVAP (evaporative emissions) leak codes
The evaporative-emissions system seals fuel vapour and burns it in the engine. A leak — anything from a loose fuel cap to a cracked hose or a stuck purge/vent valve — sets these codes. They won't hurt the engine, but they'll fail an emissions test, so start with the cheap, common cause: the fuel cap.
Emissions fault — safe to drive; check the fuel cap first.
Common causes
- Loose or damaged fuel cap
- Cracked EVAP hoses or filler neck
- Purge or vent valve stuck
- Leaking charcoal canister
First checks
- Check the fuel cap seal first
- Smoke-test the EVAP system
- Command purge/vent with a bi-directional tool if supported
System: Auxiliary emission controls. This is general guidance for the generic OBD-II codes in this group; always confirm against the service information for your specific vehicle.
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