Circuit Description
WARNING: This page is about a different car, the 2002 Lexus GS 300. However, it is still accessible from the selected car via links, so may be relevant.
To reduce HC emissions, evaporated fuel from fuel tank is routed through charcoal canister to intake chamber for combustion in cylinders. ECM changes EVAP system Vacuum Switching Valve (VSV) duty signal so intake quantity of HC emissions is appropriate for driving condition (engine load, engine speed, etc.) after engine is warmed up.
DTC P0441 is set if pressure in charcoal canister does not drop, or pressure dropped more than specified limit during purge control. Possible causes are:
- Disconnected, damaged or blocked vacuum hose.
- Fuel tank cap incorrectly installed, cracked or damaged.
- Open or short in vapor pressure sensor circuit.
- Faulty vapor pressure sensor.
- Open or short in VSV circuit for EVAP system.
- VSV for EVAP system.
- Open or short in VSV circuit for canister closed valve.
- VSV for canister closed valve.
- Open or short in VSV circuit for pressure switching valve.
- VSV for pressure switching valve.
- Fuel tank cracked or damaged.
- Charcoal canister damaged.
- Fuel tank overfill check valve cracked or damaged.
- Faulty ECM.
NOTE:
If DTC P0441, DTC P0450 or DTC P0451 is output after DTC P0440, perform appropriate circuit test first before performing DTC P0440 test.