OBD-II code guide
P0440 EVAP System Malfunction
P0440 means the evaporative emissions system failed a general leak or flow test.
What it means
The vehicle cannot confirm that the fuel vapor system is sealed and operating normally.
Common symptoms
- Check engine light
- Fuel smell
- No drivability issue
- Failed emissions test
- Hard start after refueling in some cases
Likely causes
- Loose fuel cap
- Cracked EVAP hose
- Purge valve problem
- Vent valve problem
- Charcoal canister issue
First checks
- Inspect fuel cap first.
- Look for damaged vapor hoses.
- Note whether the code appears after refueling.
- A smoke test may be needed.