hi name is brandon new to this site and im needed some advise here with my truck. I bought a 2006 f150 fx4 it has the 5.4 liter in it. When i bought it i already new it needed a tune up just by they way it drove it had no power and it would backfire at high RPM. So long story short i spent a day and changed the plugs and all 8 coil packs and i used all motor craft plugs and coil packs. After i did that it was like night and day difference ran like a dream. Well now about two weeks later i started to notice that it was idling rough not bad but just enough to notice that it was. Check engine light came on and i hooked up my scanner and it was giving me codes-PO316&PO300 and PO1000. this is where it gets weird i unhook my scanner and start the truck and the light was off im okay great i just left it alone. Three days later while i was driving to work the light came back on and was giving me the same three codes. Im at loss where to start now

 

you have a random misfire, misfire on startup, and initial checks not completed on startup. I would worry about the first two "misfires". You don't have a specific cylinder narrowed down.. It could be a specific cylinder or it could be the shaft position sensor that is giving bad timing / fire... You can try the sensor, or keep running until you get a specific cylinder code , if ever.