diagnostic trouble codes

[my01cam]

CEL came on so I decided to go use the loan scanners at autozone. After hooking up the scanner it was showing that there was three possible troubled areas, the code showing on the screen was P0440=EVAP system malfunction. At this point I decided to erase the code so I could get to the next two codes. BIG MISTAKE. I guess by now you figured what this d--- ---- did, big time operator malfunction. I ended erasing the remaining codes before viewing.
My questions:
1. Would the other codes be in the same EVAP system (P0440)?
2. Will the CEL come back on again if the problem continues? would like to scan again and get all the codes.
3. Can I bring back(unerase) the codes? The scanner I used at autozone appears not to have this capabilty. If this is possible what type of scanner do I have to use?

forgot to mention it a Camary 2001 V6 LE
l
THANKS
my01cam

[Mike Gerber]

1. Possibly, but there is no way to tell now.

2. Yes

3. No

Mike

[STANJ]

possibly P0440,P0441,P0446. Those 3 often comes together when you have a faulty emmision system. If you drive the car more, the code will reappear.

[my01cam]

The CEL came on again. So, back to Auto Zone for the loaner code reader and came up with 3 codes. the first two were both P0440 and the third was P0446. My Haynes manual specifies that the possible problem area for P0446 was same as P0441. Between P0440 and P0441 there are a total of 14 possible problem areas. I would like to know what I'm up against in trying to locate the actual problem area. The P0440 appears to be fairly easy for the most part. But P0441 is specifiying trouble areas like open or short circuits, sensor malfunction etc. it appears that P0441 is more envolved.
Is here another test I can do on my driveway to narrow the list of trouble areas or is this a major problem that need to go to a repair shop or dealer?
Would highly appreciate any suggestions and recommendations you could provide.
Thanks

[Nad1370]

Gas cap loose will set all 3 codes 440,441,446.
Meaning the system has a leak and can't pressurize/hold vaccum.

Also a malfunctioning tank by pass valve in the charcoal canister will set a 446 and /or a 440.
Malfuntioning vsv located by the air filter box will usually cause a 441 only.

[my01cam]

Originally Posted by Nad1370

Gas cap loose will set all 3 codes 440,441,446.
Meaning the system has a leak and can't pressurize/hold vaccum.

Also a malfunctioning tank by pass valve in the charcoal canister will set a 446 and /or a 440.
Malfuntioning vsv located by the air filter box will usually cause a 441 only.

The code reader gave me 440 and 446 only, so I'll take a shot at the tank bypass valve. I only refered to 441 cause the manual says trouble area in 446 was same as 441.

1. After I replace the tank by pass valve do I have to clear the codes?
2. How long do I have to operate the car before I know the problem was fixed?

Thanks

[keithy]

basically, those 3 codes leads to a faulty vsv. replace the vsv near the charcoal canister. I had the problem, and replacing the vsv got rid of the cel. No need to reset, coz it will dissapear by itself. But if you really want, you can disconnect the battery terminal for a while and it should be all good.

[ween13]

what is a faulty VSV ? Please.