Ran fine last night, wouldn't start this morning

Beware! Mine is doing the same thing right now. It has ran great for a month. All I did to get it to start that time was switch to my spare ecu and then switch back. (which ranks right there with all plugs fouling at once) Went out today left it outside and no fire, first time in a month it has done this. Supposed to be 105 degrees tommorow, hopefully it will start in the morning. I have changed plug wires coil cap and rotor ecu you name it. It must be a wire or my ignition switch. Mine won't start when I try to jump at relay...