P0442 Toyota Corolla
EVAP System Leak Detected (Small Leak) · Powertrain Code · Low · Repair: Easy
What is P0442?
A small leak has been detected in the EVAP system. Common causes include a loose or cracked gas cap, cracked EVAP hose, or faulty purge/vent valve.
When the Toyota Corolla triggers code P0442 (evap system leak detected (small leak)), it typically points to an issue in the powertrain system. Below you'll find the most common causes, symptoms, and repair options specific to the Toyota Corolla.
This repair is rated easy, meaning basic tools, no lift needed.
Diagnostic data on this page is compiled from publicly available repair resources and technical service bulletins. Always have a qualified mechanic confirm the diagnosis before authorizing repairs on your Toyota Corolla.
Common Causes on Toyota Corolla
- Gas cap seal worn or not clicking properly
- Charcoal canister micro-crack causing small vapor leak
- VSV (vacuum switching valve) for EVAP not sealing fully
- EVAP vapor hose deterioration near fuel tank
- Fuel tank overfill check valve malfunction
Symptoms
- Check engine light illuminated
- Faint fuel smell near vehicle
- Slightly reduced fuel economy
- Failed emissions test
- Occasional rough idle after refueling
Notes for Toyota Corolla
Toyota charcoal canister and VSV valve are the most common causes of P0442 on Camry and Corolla after ruling out the gas cap.