Help!! Codes p0449,p0455

[Arb]

Hi there guys. This is my firts post here I have a 2009 GMC Sierra 4.3 and I have the codes p0449,p0455. I want to found the solution of this problem because is killing me I ready change the evap solenoid with the filter, even the gas cap and the code is still there do you know what else could it be. Thank you

[Dnt]

You cleared the code and it came back on correct??

I changed mine out on a 2009 SLT and the solenoid came with a new vent hose, did you change out that vent hose per instructions or did you shortcut and reuse the old one?

[Arb]

Yes I change the old hose for a new hot water hose 5/8 and the code still there, what else I could be?

[Mike GMC]

Did you clear the code or are you expecting it to go away by itself? If the problem is fixed, it will eventually clear itself, but if you want it gone now, you must use a scanner to clear the code.

[DSGB]

I would start with the EVAP purge valve

[Arb]

Did you clear the code or are you expecting it to go away by itself? If the problem is fixed, it will eventually clear itself, but if you want it gone now, you must use a scanner to clear the code.

Yes I clear the code but when I start the truck the code is back

[Arb]

I would start with the EVAP purge valve

Where is located that piece

thank you for you help guys

[Arb]

Any help would be appreciated

[tbarn]

Forget the purge valve for now. P0455 is likely a result of the P0449. The 449 code is the vent valve, ECM or wiring. P0443 would indicate a purge valve. It is very rarely an ECM. Given that you replaced the vent valve, it's time to look at wiring. It will be harder without a proper scanner but can be done.

[muddkatt]

Purge valve is only about $15.00 and they DO FAIL. I would start with it just to eliminate the possibility. Correct one is ACDELCO 2141473

[Arb]

I ready change the purge valve and check the wiring to the valve solenoid and their is no power on the wire so I guess the problem is electrical do you know if this wire comes from any fuse or relay??

[tbarn]

I agree, purge valves DO fail. But will NOT set a P0449.

[tbarn]

Here is a wiring diagram

p0449 07 classic.pdf

p0449 07 classic.pdf

p0449 07 classic.pdf

p0449 07 classic.pdf

[tbarn]

You might want to check under the underhood fuse box. Have seen a lot of rodent damage there.

[Arb]

Thanks for you help I was concern if this diagram is the same for the 2009 4.3