P0455 code on 05 Tahoe

Ok it all started a week ago when i accidentally left my gas cap off at the gas station(bought a tether and new gas cap)...the tighten gas cap prompt went away...then the next day i get a check engine light. I go to Auto Advance and get the code checked and its p0455...so i purchase the required part PV424, installed it and disconnected the battery for 30 mins and everything was good...two days later the check engine light comes on again and its the same code... i understand that this is all emission stuff and my truck is running great...any help would be appreciated..

My understanding is it’s a check valve on the fuel tank that goes bad from over filling the tank, my 05 Denali has the same code and I haven’t bothered with it lol.

I don’t know about the Tahoes but on the trucks the tank canister vent valve rust sand breaks open

Sometimes it's even just a disconnected hose near the filler neck.

If you have someone that can run a system check using a diagnostic reader/scanner, it should help to determine if it is an electrical or vacuum issue. Snapon type of equipment, not the cheap 50.00 scanners.