Truck wont start.....?

Okay drove the truck to the shop to do some body work. It drove fine there and back. A buddy and myself then took it out that night for some grub. Ran fine there. When we went to leave it cranked longer than normal and when it fired the idle was high and erratic. It finally smoothed out and drove home fine. The next morning it will only crank over and does not fire off. The fuel pump is pumping and no fuses are blown. I had the ground disconnected when I was ever welding also. How do you check for spark on a coil pack engine? Any help is appreciated. Sorry for the book. JR

what truck and motor

Oh sorry, 04 to new F-150 4.6 2wd. supercrew shortbox.

Also will an obd2 scanner tool work if the truck wont start? Does it retrieve codes when the key is on only too? THanks.

Same type thing was happening with my GTI try starter fluid if it starts its a fuel issue. I changed the fuel filter and the hose to the fuel pressure senser it has not done it since. It worked for me just trying to help.

Yes, a scanner will still show codes even if it doesnt start, I also wouldnt think that all coil packs would take a dump at the same time. Try pulling #1 coil pack out and placing a small screwdriver in the wire and hold it close to something that will allow it to jump to ground. If it sparks its not the coil packs.