P0442
OBD-II code guideSmall leak detected in the EVAP system
Learn what the P0442 small EVAP leak code means, the common causes, how serious it is, and what to check next.
Plain-English meaning
What the signal is telling you
The evaporative-emissions system is not holding pressure as expected, but the leak is small. The vehicle may drive normally while the warning light stays on.
Typical severity
How quickly to act
Low — diagnose when practical
Severity depends on how the vehicle is behaving and which other codes are present.
Likely causes
These are starting points for inspection, not an automatic parts list.
- A loose, worn, or incorrect fuel filler cap
- A cracked EVAP hose or vapor line
- A purge valve or vent valve that is not sealing
- A leak around the charcoal canister or filler neck
Possible symptoms
Symptoms vary by vehicle and may have more than one cause.
- The check-engine light may appear while the vehicle drives normally.
- A fuel-vapour smell may be noticeable near the vehicle.
- There may be no obvious symptom beyond the warning light.
Practical next steps
Give the technician useful context before replacing anything.
- 1Check that the fuel cap clicks tight and inspect its seal for damage.
- 2If the code returns, ask for an EVAP smoke test rather than repeated code clearing.
- 3Treat fuel vapors or a strong fuel smell as a reason to stop and arrange an inspection sooner.
Have this code on your dash?
Turn the signal into a useful report.
Add your vehicle and symptoms so PitPilot can help identify the right first inspection.