P0442
Get Serviced SoonFix: Low — can wait, but don't ignoreEVAP System Leak Detected (Small Leak) — A small leak in the evaporative emissions system, often the gas cap.
Dashboard light triggered
Check Engine LightWhat to do
Tighten or replace the gas cap first — it's the most common cause. Clear the code and see if it returns. If it does, have the EVAP system smoke-tested.
Common causes
- Loose or faulty gas cap
- Cracked EVAP hose
- Faulty purge or vent valve
- Leaking charcoal canister
Estimated repair cost
$0–$300
Exact cost depends on the cause, your vehicle, and labor rates in your area.
What to tell your mechanic
Use this script so you sound informed and get a clear diagnosis before agreeing to repairs:
“Code P0442, EVAP small leak. I've already tried a new gas cap. Can you smoke-test the EVAP system to find the actual leak?”
About the Check Engine Light
Code P0442 triggers the Check Engine Light. Indicates an issue with the engine or emissions system. Could range from a loose gas cap to a serious engine misfire.
Read full Check Engine Light guideFrequently asked questions
- What does OBD code P0442 mean?
- EVAP System Leak Detected (Small Leak) — A small leak in the evaporative emissions system, often the gas cap.
- What dashboard light does P0442 trigger?
- P0442 triggers the Check Engine Light.
- How serious is P0442?
- Severity: yellow. Fix priority: Low — can wait, but don't ignore.
- How much does it cost to fix P0442?
- Repair costs typically range from $0–$300. The exact cost depends on the root cause and your vehicle.
Related OBD codes (same dashboard light)
These codes also trigger the Check Engine Light: