OBD-II code guide
P0442 Small EVAP Leak Detected
P0442 means the EVAP system has a small leak, often too small to see without testing.
What it means
Fuel vapor containment is leaking slightly during the system self-test.
Common symptoms
- Check engine light
- Usually no drivability symptoms
- Possible fuel smell
- Emissions inspection failure
Likely causes
- Fuel cap seal leak
- Small cracked hose
- Loose vapor line
- Vent valve leak
- Canister leak
First checks
- Tighten or inspect the fuel cap.
- Look for cracked rubber lines near the engine bay and fuel tank.
- Do not keep replacing caps if the code returns.
- Ask for smoke testing if no leak is visible.