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EVAP code PO449

Avie

Full Member
Joined
Jul 18, 2005
Messages
70
Location
Pinellas Park, FL
Got a trouble code PO 449, EVAP emission control system vent/sol malfunction...

I believe I just need to replace the cansister and valve??? I think its GM p/n: 25932571 Or can I get that at autozone or advanced?

Never replaced one but want to make sure this is the right part for this code.

thanks!!  ???
 
Just out of curiousity, have you replaced the gas cap with a locking one recently? I put on an aftermarket cap that didn't fit worth a crap and I think this was the error code I got from it. Replaced it and had the dealer reset the trouble code.
 
I reset the computer last night with my scan tool and this morning, it didnt trigger check light..

I'm hoping i'm good now. But I'll check the gas cap and get a new one anyways..


:)
 
any starting issues?  Running issues?  Mine threw a similar code (dont recall exactly).  I posted in this section somewhere.  Mine would be difficult to start after a fill up.  And an occasional rough idle.  Gas cap is a cheap place to start.  Apparently its an issue with some avs
 
Well I replaced my gas cap, reset the computer and drove around. restarted the truck again, and theirs the light again. same code..  :mad:

any suggestions? Dont want to go to the dealer, kinda broke these days..  :needhug:
 
sounds like you have a bigger issue ... I would take it to dealer and see if you can get more information on the code from the parts department ....

here is what I found:

P0449 Evaporative Emission Control System Vent Valve/Solenoid Circuit Malfunction

sound like you need to replace a circuit ....
 
i talked to the parts department and they said Vapor canister purge solenoid in the Av are being replaced alot. The solenoid is being replaced by a new verison design. (that tells me this is a flaw if alot of them are being replaced)

Also theirs two verisons of this unit, old style which cost $40 and a newer style which needs a bracket, connector and unit for $150 !!  :(

I haven't looked yet on which verison I have, hopefully the cheaper one, but i'll find out tonight and look at it.

Their is a technical bulletin on this but no recall as of yet. This is located in the rear near the gas tank. I'm going to replace it and hopefully should correct this problem.

 
Just had the same code PO449 on my 2007 Avalanche.  Purge Vent Solenoid Bad.  Part # 25962086.  Still under warranty so no cost to me.  Hope this helps.
 
I too have received the po449 code.  Have 50,000 on a 2007.  Read the threads about trying to fix the problem.  Question I have is, what are the consequences of ignoring the warning light?  Truck seems to run fine.  Don't really have the money to take it into a gm dealer to diagnose further.  the lights gone off once but came back on within the same day after 5 or 6 engine starts.  I guess I could try some of the fixes or replace the gas cap or solenoid without incurring too much expense.
 
:welcome: to the club downindetroit have you tried changing the gas cap or at least cleaning the seal area.

BTW I'm up in Southfield. :wave:

PS it is never good for the engine to be running with the light on get it fixed as soon as you can.

PPS click on the blue line at the bottom of this post and say hello to the rest of the Michigan Crew
 
That part is $37 at the dealer.  its not to hard to put on just drop the spare tire.  now when you go to the dealer make sure they give you the one with the hose that goes to the evap canister. the part number comes up with the hose r without. you need the hose attached . thrust me.  i  went through two of them  not knowing this.
 
I tried the gas cap swap and the code remained so tomorrow I'm going to get into.  At first
i was considering trying to clean it but if the parts reasonably priced there's no sense doing it twice.  Might as well put on the new part  Thanks for the help!
 
Avie said:
i talked to the parts department and they said Vapor canister purge solenoid in the Av are being replaced alot. The solenoid is being replaced by a new verison design. (that tells me this is a flaw if alot of them are being replaced)

Also theirs two verisons of this unit, old style which cost $40 and a newer style which needs a bracket, connector and unit for $150 !!  :(

I haven't looked yet on which verison I have, hopefully the cheaper one, but i'll find out tonight and look at it.

Their is a technical bulletin on this but no recall as of yet. This is located in the rear near the gas tank. I'm going to replace it and hopefully should correct this problem.
 
I see that you swapped the gas cap with a new one? did you clean the neck filler where it goes? The only other thing would be one of the hose's pinched underneath by the spare tire or the air valve is not as high as possible?

When I change mine all I out like this, piece by piece I was frustrated and lost patience as I got the codes to clear but first time I went to fill up they came back. I went back up underneath and the air valve near the gas filler was kinked and I re-place the air valve and hose attached all nice and neat to the highest point I could reach, if you remember its longer then needed. I zip tied the valve all the way up as high I could get it and laid the hose nice and neat without kinks, I also notice the gas smell was strong in this hose. I also notice in my hast of installing, I kink the one of the hose's going to valve leading to the gas tank. This stop the codes until I found the valve leaking on top of the gas tank? but you have not stated anything of smelling gas or leaking gas from the tank.?
 
I have not replaced the gas cap. I was told if it was the gas cap it would be a different code. P0446 I believe? I did tie the everything nice and neat, but it would not hurt to double check. I am not smelling any gas maybe a little at start but it disappears fairly quick.

Should I go ahead and replace the gas cap?
 
:help:Anyone have any suggestion on this P0449 code. I have replaced gas cap, canister and jumper wire in the back, also the purge valve on the manifold. After all this clear codes and engine light is right back on. No hoses are pinched everything sames to be in place.
 
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