Hi,
I have a 2001 Chevy Malibu with the error code PO446. It turns on the check engine light, but when I scan it, the code is inactive and have to refresh , then delete it from it's history status to turn off the check engine light. I've changed the gas cap and the EVAP value already. This happens only about once a month. Any help will be appreciated. Thanks
Jim

 

Code P0446
EVAP Emission control System Vent Circuit Malf

Look up this P code to see how to repair it.
P0446 Evaporative Emission Control System Incorrect Purge Flow

Hope this helps you
John

 

Check out the purge valve Solenoid Under the rear of the car byt the Evap canister. its easy to take off hook a Small Sqaure 9 volt batter up to it and see if it clicks if it does it means its working. and it may be in the wiring