Was running turned it off now it will not start. It's getting gas and spark

Check and see if there is pulse on the injectors. It sounds like it could be your anti-theft system. Another possibility is your timing chain jumped when you cranked it.

Just replaced a timming chain on my 1998 F-150 4.2L. It was getting fuel to the plugs and was firing. Big key to timing was it backfired while I was trying to crank it?