Well, I'm slowly chasing down this issue. sometimes at wot, my truck backfire and hesitate for a couple of seconds then picks right back up. I changed my plugs, 8000 miles ago with the sp515. Replace all 8 cops with motorcraft today because I got a good deal (189 for all 8). Noticed a plug backed itself out. Pulled it out and noticed it was fouled. Replaced and backed out again. So I bought a torque wrench and torqued it down. Replaced maf, cleaned tb and changed fpdm. Still hasn't fixed it. Noticed green corrosion? On the welds on fuel rail around the pressure sensor and on the other part right behind it. Could a bad fuel pressure sensor cause this? Not sure about the green stuff on the fuel rail. Also my throttle body makes a click sound when it opens at wot. So I tried to replace the throttle position sensor to just break a bolt. Lol so any help would be awesome!!

 

Also changed cam postion Sensors too. After doing this, I picked up quite a bit of power now it's just fixing the mis/hesitation issue. It's driving me crazy!

 

Please tell me you also put in a new fuel filter at some point!
I'm guessing you did it but forgot to mention it.
If not, that is a lot of work that could maybe have been avoided.

 

Yeah I have replaced it as well. First thing I did lol.