RE: Error Code- P0441 Evaporative Emission Control System Incorrect Purge Flow
If the gas cap doesn't cure it, crawl under the drivers side just behind the cab, the charchol canister and connection hoses are there. If any are loose or cracked or even seem like they might leak, replace them. This has been an ongoing annoying little problem that seems to crop up after the truck is a couple of years old. This summer I intend to replace mine with silicone hoses. Mine has seen a lot of salt and slushy snowy roads this year and I suspect it will be my turn soon.