The leak test found a very small leak in the fuel vapour system. The driver usually sees only the engine light.
Causes vary by car. Test before you order a part.
Likely causes, most common first
- Worn fuel cap seal
- Tiny crack in an EVAP hose
- Slightly leaking valve
- Leak at a canister or tank seal
Parts usually involved
- Fuel cap Find at suppliers
- EVAP hoses Find at suppliers
- Vent valve Find at suppliers
- Charcoal canister Find at suppliers
Test before you replace
Inspect the cap seal, then smoke test carefully since a very small leak can be hard to see.
General guidance for generic OBD2 codes. Always follow the maker's procedure for the car in front of you.