2003 toyota Matrix code p0441 and p0446...need help

Check and make sure your gas cap is screwed on tightly. Then, check the vacuum lines are attached correctly and not leaking. I would bet one of the hoses came off or you have a hole in one or more. The hoses split with age. Start with these, before changing sensors or solenoids.
http://www.obd-codes.com/p0446
http://www.obd-codes.com/p0441
http://www.obd-codes.com/p0442

code p0440 refers to evaporative emission (EVAP) system--malfunction=== causes --hose connections --intake leak--EVAP canister purge valve
code po441 refers to EVAP --incorrect flow detected==causes the same as for po440
code po446 refers to EVAP system vent control --circuit malfunction===causes --wiring---EVAP can purge valve--ECM
generally I would replace the purge valve as it is common to all codes

According to my 2002 Toyota Tundra manual (and it may be different for your car) P0125 is as follows:
Insufficient Coolant Temperature
for Closed Loop Fuel Control

This would seem unrelated to your original problem.

Do a smoke test...

Both codes are with the EVAP SYSTEM, there are numerous items it could be. A repair shop that does Toyotas or the delaler would be the best to check it out for you. Its not anything that will leave you walking or disable the car.

where is Evap Emission Control System Purge Flow fault

P0440= Evap Control Sys Malfunction
P0441= Evap Control Sys Purge Flow Fault
P0446= Evap Control Sys Vent Ckt Malfunction

P0420 indicates you have a catalyst efficiency issue; replacement of the Air-Fuel Sensor should take care of that;
The P0441, P0446 and (I assume P0440); you said 446 twice, indicates a faulty or loose fuel cap; it is not sealing properly.
Please feel free to respond to me if you have any further questions.
A FixYa rating from you regarding my assistance would be greatly appreciated.

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.