440,446 trouble code 97 max !HELP!!!

I recently bought a code reader for my car.The engine light was on, so I ran the test and it gave me these numbers 440 ,446. I know what the manual says about it( Evaporative emission control system) :banghead: . But if anyone knows what to do to fix the problem it wouold be very helpful to me :2cents: . My sister has a 96 max with another problem. Her problem code comes up as 325(knock sensor bank 1). I think she needs a new (front) o2 sensor, but I'd like to be sure before I tell her to spend $80 bucks on one.

replace the vent control valve on the evap canister for 440,446 replace knock sensor for 325 which requires intake manifold removal also sometimes on these cars the evap pressure sensor might be giving a false reading for the vent control valve in which case you need to replace the pressure sensor. i recommend taking it to the dealer

Thanks, I ordered a new vent control valve. I'll write back with my results. As for the 325 code, Taking apart the exhaust manifold seems difficult, but I'm pretty good with this stuff. So I'm going to research how to do it further. Then take it from there.If you know anything else helpful please reply. :smokin:

I'm replying to give an update. I replaced the vent control valve. My check engine light came back on though. The 446 trouble code is no longer only 440 is coming up now. What else do I have to do? Do I need a new gas cap?Somebody please help!!!