454 Wont start.

1999 K3500 7.4

Truck will sit for weeks without starting but occasionally it will chug vary slow and even rotate back words a 8th turn and than it will fire and run great no issues for a month to six. Nothing changes I have replaced everything
Sensors: cam, crank, map, o2, mass air, ambient air, knock.
Also, the computer , coil, cap, wires, plugs,

I don’t know what else to do it is not starting right now

Post up tune. Then next time it starts do a log while it is running. Have you confirmed the fuel pressure is good?