i have a 1995 explorer...recently purchased off of a friend and was running very good but i always replace wires and plugs when i purchase a new vehicle. once i put them in it started missing very bad. i took the plugs out and noticed #5 cylinder plug was charred black...what does this mean? clogged injector?

 

I would you recheck your work. Could you have pulled on one of the plug wires and opened the connection? Did you check the plug gap before installation?
Usually the black is caused by an excessive rich condition or plug not firing.
You might try swapping the plug with another cylinder and see if the miss goes with the plug. Let us know what you find.