1996 engine hesitation,knock and smoke

The engine is for the most part is stock.
Yesterday ,09/14/2004, It began to hestitate when accelerateing in hgih gears every once in a while. Assumed I had put some bad gas in it or had some carbon build up, as the car is not driven alot, I put in some octane booster/ injector cleaner.
Today .09/15/2004, the hesitation has gotten worse, engine has started knocking and it is now blowing smoke.
Any ideas, sugggestions, TNT or C4 ?
Thanks

Not white
Ford Techs have trouble shoot it and say that
the Pplugs and wires need to be changed and that the vaccum line to the EGR valve needs to be repaired and the engine needs to be decarboned