will not start seems to be fuel delivery or maybe something electrical on 2006 Nissan Xterra

It seemed as if it ran out of gas so i put some gas in it now it still will not start i have check fuses and relays i pull the fuel line off i know the fuel pump works the spark plugs were pretty burned out i repaced those i dont know what else to check please help

1 answer
Hi,
You will need to verify that the spark plugs are firing and the fuel injectors are opening. Can you do this?