P0442 Honda Civic
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 Honda Civic 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 Honda Civic.
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 Honda Civic.
Common Causes on Honda Civic
- Gas cap O-ring worn or damaged
- Fuel tank pressure sensor reading false small leak
- EVAP canister vent shut valve not closing fully
- Small crack in EVAP line near fuel tank
- EVAP purge control solenoid slow leak
Symptoms
- Check engine light illuminated
- Faint fuel smell near vehicle
- Slightly reduced fuel economy
- Failed emissions test
- Occasional rough idle after refueling
Notes for Honda Civic
Honda fuel tank pressure sensor failures are a common cause of P0442 on Civic and Accord. The sensor is located on top of the fuel tank.