Engine and gearbox (P)
P0442: EVAP small leak detected
The evaporative emissions system has detected a small leak. This system prevents fuel vapours from escaping into the atmosphere.
Checked by a licensed car technician · last reviewed 29 September 2026
Symptoms
- Check engine light on
- Slight fuel odour
- Decreased fuel efficiency
Common causes
- Loose fuel cap
- Split EVAP hose
- Purge valve leak
How to check it yourself
- Ensure fuel cap is tight and seal is intact
- Inspect EVAP hoses for splits or damage
- Perform a smoke test on the EVAP system
Can I keep driving?
The car can still be driven, but it is advisable to fix the issue to avoid emissions problems.
General guidance, not a professional inspection. Confirm faults with measurements before buying parts, and use a qualified mechanic for brakes, steering, fuel leaks, airbags, and other safety-critical work. Terms and disclaimer