What would cause my 2000 Ford Ranger too miss its like the the plugs are fouling out but there's no way there new

bad plug wires (arching), crank sensor, Fuel injectors dirty or computer issue or wire harness or cam sensor, coil. Fuel filter or pump. Low compression. ect.

Your heads, my 02 ranger 3.0 doing same thing I replaced plugs, wires, fuel injectors,coil,fuel filter,intake manifold gaskets upper and lower, valve cover gaskets, throttle position sensor,cam sensor/sync. And still misfiring and running crappy. Did a drop down test and it showed 3cyldr. Won't hold drops very quick, 2 cylinder starts to drop but not near as fast as 3. So check your heads because what I've read up, 3.0 ltrs are notorious for this problem. Don't spend tons of money like I did for nothing.