TESTED VALVE OK BUT MIL STIL CIMIN ON OFTEN

Question

po446 code came on corolla 2001. tested the solenoid valve with 9v valve is working fine the reading in EVAP EMISSION CONTROL SYSTEM VENT CIRCUIT MALFUNTION What else should I do?

Answer 1

P0446 Evaporative emission control system vent control system malfunction

Try this  If this engine has a MAF (mass air flow) then this diagnostic tip would not be valid If this enigne does not have a MAF, check the condition of the air duct from the air filter to the throttle body. if there is any torn there , the EVAP vent would not be able to do its job .

 Here on this Toyota which is equipt without a MAF sensor , a torn like this would set a EVAP code, the reason the VSV valve which is attatched to the air duct would not have the proper air induction for the EVAP vent solenoid  to operate as designed.