09 f150 screw 5.4l. 96,000 miles all original everything.

A few weeks ago I had an issue while driving normally the truck began to shutter and while idling it shut off. I had a quarter tank so I Got to a gas station where it stalled again. This time it wouldn't start. Go to fuel it up and there's either a huge vacuum or pressure on the tank. That releases and I fuel up. I had to floor it to start it and pedal it to keep it going. It cleared up and went away for weeks.

now its back and I have a check engine code. Pictures attached po456

The truck stalled at a light again today. I went to fuel up and ut won't let me put in more than a tenth of a gallon at a time without shutting off the pump. It asks begins to run down the fuel filler line.
I've seen a few posts on here but not a lot of resolution. Can someone suggest a fix that they've seen work.

 

I have a 2011 F-150 5.0 that had similar problems. The PO456 code was due to a stuck vapor canister purge valve. I sprayed a bit of carb cleaner in it and cured that problem, or you could replace the valve. I had the same issue with my 2011 Ford Edge and I replaced that purge valve.

As to the fueling issue, mine would suddenly have the fuel gauge and Miles to Empty start dropping and sometimes stall the engine. This was a problem with the fuel pump/sending unit. I had Ford replace the unit under my extended warrenty.

Hope this info helps!!

 

If you can't put fuel in the vent line is blocked. It would be the small one running next to the filler tube. I haven't fixed any on this year F-150 but many others.