ok I have a new to me F250 5.4 and it will not take the fuel but very slow. I have read all types of fixes and was looking for the best one and easiest one. New check valve? new char. tank? anything?? Thanks Todd

 

This is a very common issue, and there was even a TSB on it. You can do a search of this forum and find a lot of past threads on it.

Do an advanced search, using "vapor canister" as your key. Came up with 58 threads for me, and I know the issue is covered in those. If you haven't guessed, the issue is with the vapor canister.

 

Welcome to FTE, tar ford! You didn't mention what model year your truck is, but here is the TSB that BIll mentioned:

https://www.ford-trucks.com/tsb/full...p?tsb=06-19-15