P0442 — EVAP System Leak Detected (Small Leak)
Low severityWhat it means
The evaporative emissions system, which captures fuel vapours from the tank, has a small leak. Fuel vapour is escaping to the atmosphere instead of being stored and burned. The most common cause is simply a loose or worn fuel cap.
Common symptoms
- Usually only the check engine light
- Occasionally a faint fuel smell near the car
Likely causes
- Loose, damaged or worn fuel filler cap (most common)
- Cracked or aged EVAP hoses
- Faulty purge or vent valve
- Damaged charcoal canister or filler neck seal
What to check first
- Remove and retighten the fuel cap, inspect its seal, then clear the code and see if it returns
- Inspect EVAP hoses around the charcoal canister
- Test the purge and vent valves
- Have a smoke test done to locate small leaks
Can you keep driving?
Safe to drive. It is an emissions fault rather than a mechanical risk, but it will fail an emissions inspection.
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