P0455 on Tahoe 2007

[Faustof]

Hi everyone, I have a P0455 code on my 2007 Tahoe, the thing is that I erase the code with my small scaner and it works fine for few days, so I belive there is no leak on a hose (my guess) because if there where a constant leak (craked hose kind), so I belive is the purge valve or the fuel cap. I read that most times the problem is the purge valve since it has more moving parts. Any help wil be appreciated.

 

[Fless]

Moved you here from the 2021+ section.

Note that the evap cycle runs only from a cold engine, and when certain other conditions are met. Fuel level between 1/8 and 7/8, IAT and ambient temp close (within around 14 deg F or so, IIRC), etc. etc. etc. So it's not going to run every time you start the engine. It'll set a Pending code the first time it fails and you won't see that except on a scan tool. On the second failure it will set the CEL. That could take several days just to work through having the correct conditions to run the evap cycle, and for it to fail twice.

There are many potential causes: a failed gas cap, leaky vent valve, plugged charcoal canister, evap lines plugged with charcoal from a failed charcoal canister, or a failed purge valve on the engine to name a few.

YouTube is your friend; there are plenty of troubleshooting videos out there on the P0455.