P0440 OBD-II Trouble Code - Evaporative Emission Control System Malfunction
Trouble Code P0440 indicates that your 2003 Toyota Corolla's EVAP control system has a problem. Your Toyota's EVAP system consists of many parts, including the gas cap, fuel lines, carbon canister, EVAP purge valve, and other hoses.
The EVAP system prevents the escape of gasoline vapors from a vehicle's fuel system. Fuel vapors are routed to the EVAP charcoal canister for storage. Later, when the engine is running a purge control valve opens allowing intake vacuum to siphon the fuel vapors into the engine.
What can trigger a Trouble Code P0440?
A code P0440 could mean one or more of the following has happened:
* The gas cap is not installed or working properly
* The purge solenoid has failed
* The canister is plugged and not working properly
Here are a few solutions for clearing trouble code P0440:
* Remove and reinstall the gas cap. Have the computer codes cleared and see if the check engine light returns.
* Inspect your Toyota Corolla's EVAP system for broken or disconnected vapor hoses
* Inspect for damaged or disconnected hoses around the EVAP purge solenoid
* Check and/or replace the EVAP pressure sensor
* Check and/or replace the EVAP purge valve
