Detail: With a P0446 OBD-II trouble code, here are some things to try: Replace Vent valve Repair open, short, or resistance problem in control circuit Repair open, or short, or resistance problem in power circuit Replace PCM Other EVAP DTCs: P0440 - P0441 - P0442 - P0443 - P0446 - P0453
Solution: Hi, a 6ya Mechanic can help you resolve that issue over the phone in a minute or two. Best thing about this new service is that you are never placed on hold and get to talk to real repair professionals here in the US. click here to Talk to a Mechanic (only for users in the US for now) and get all the help you need. Goodluck! , These codes are all for the Evaporative Emissions System. P0440- Evaporative emissions system fault- just saying there's something wrong with the system. P0441- Evaporative emissions system- Incorrect purge flow- saying that the system isn't purging the raw fuel vapors (hydrocarbons- HC) as well as it should. P0446- Evaporative emissions system- Control valve circuit low- there is a valve, usually located on the charcoal canister at the rear of the vehicle, that opens to allow fresh air to enter the evaporative emissions system as the engine vacuum purges the fuel vapors from the charcoal canister and closes when purge is not needed to prevent leakage of those fuel vapors to the atmosphere (HC is a greenhouse gas and is regulated as such by the fed gov't). Given that you have the incorrect purge flow code and the control valve code together, my bet is that the vent control valve has failed (causing the P0446) and is not opening to allow fresh air into the system to displace the air from within the system that is being pulled to the engine. Since you have no fresh air entering the system, the engine will pull a vacuum on the system instead of the vapors "flowing" into the engine (causing the P0441). I hope that this is helpful to you!!! ASE Master Technician with L1 and X1 Certifications; Nissan Scope Technician; Chrysler Level 3 Silver Technician- 12+ years experience. , you hav egr valve problems n evap emissions flaws-ull need a repair manual if ur the mech-buy one at a parts place-clymer n haynes r the best , P1442 usually gas cap. P1449 usually vent solenoid. P1441 usually always a faulty FTP sensor. Very problematic to Malibu, Grand Am Cavaliers and Aleros. That would be my first area to check. They are also known for poor wiring connections at the Left rear passthru connector to the fuel tank and vent solenoid, but not necessarily for that code.