My 2007 Chevy Avalanche failed the emission test with the code of P0455 what is the problem?

Here's a link to code P0455, P0455 OBD II Trouble Code Here's the link to code P0441. P0441 OBD II Trouble Code

P0449 - OBD-Codes.com

www.obd-codes.com/p0449

Detailed information on diagnosing and repairing a P0449 DTC code which refers ...P0449 Evaporative Emission Control System Vent Valve/Solenoid Circuit ... OBD-IITrouble Code Technical Description ... 2004 Chevrolet Tahoe 4.8L p0449

EVAP Code P0449 - YouTube

? 16:47
https://www.youtube.com/watch?v=AlfOSMmisPg
Mar 13, 2013 - Uploaded by realfixesrealfast
Here is a description and how to diagnose EVAP code P0449. ...Up next. Quick Easy Fix P0449 P0455 Evap Codes on ChevySilverado 2007 ...

Quick Easy Fix P0449 P0455 Evap Codes on Chevy ...

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https://www.youtube.com/watch?v=aL5KmV1d26Y
Dec 27, 2013 - Uploaded by wagslick
Quick Easy Fix P0449 P0455 Evap Codes on Chevy Silverado 2007 .... Well clearing the error codes at auto store will not prevent it come ...

Solving a P0449 Engine Code on a 2008 Chevy Impala ...

pressanykey.simplyahobby.com/.../solving-a-p0449-engine-code-on-a-2...

P0455 means a gross leak detected in the Evaporative Emissions System. Some call this a "gas cap" code, because the most common cause a loose or failed gas cap. But it could be caused by any vapor leak in the fuel tank, filler neck, or anywhere else in the vapor management system. If it isn't a gas cap, you will need tol take it someplace where they have a smoke machine that can find the leak using smoke.

The P0455 means " Evaporative Emission System Leak Detected (large leak). You can try to clear the fault code with obd2 code scanner.

Hi Rosalee_IM,
The codes your vehicle is storing are for low voltage from your accelerator pedal position sensor and a gross evaporative emission leak. The code P2122 and P2138 are directing you to test the accelerator pedal position circuit and/ or sensor. This is the cause of the reduced power concern you are feeling.The P0455 is telling you there is a large leak in the evaporative emission system. The most common cause for this code is a loose or incorrectly installed gas cap.I hope this helps clarify the concerns you are experiencing. If you'd like more information on how to trouble shoot the problems,drop me a line. Please include the model Impala you have,(LS,LT or LTZ) and the engine size. I will do my best to get back to you as soon as possible.Thanks, Chuck

P0496 is not alisted code.
P0455 - Evaporative Emission Control System Leak Detected Gross Leak (fuel vapors)
Symptoms - Engine Light ON (or Service Engine Soon Warning Light)
- Possible a noticeable fuel odor caused by the release of fuel vapors Possible causes - Missing or loose fuel cap
- Incorrect fuel filler cap used
- Fuel filler cap remains open or fails to close
- Foreign matter caught in fuel filler cap
- EVAP canister or fuel tank leaks
- EVAP system hose leaking
- Fuel tank leaking

There may be an emissions leak but a very common issue is the canister vent valve. Make sure if you contact your local dealership that you have your vehicles vin number available.

P0449 - Evaporative Emission (EVAP) Vent Solenoid Control Circuit

P0455 - Evaporative Emission (EVAP) System Leak Detected

The vent solenoid valve has been redesigned to correct the problem you are having. I would recommend purchasing the dealer component.
I am not aware of any aftermarket parts suppliers.

Hi, a P0446 means Evaporative Emission Control System Vent Control Circuit Malfunction

Full details @ http://www.obd-codes.com/p0446

A little late but check your gas cap first.

http://www.p0455.com