help before i shoot it, please!!!

[chevyndn]

i have a 1997 s-10 blazer. its just a plain jane 4.3 4x4 4 door blazer. about a year and a half ago i made the mistake if keting people drive it and since then it hasnt ran right. the biggest problem ive had to fix so far is the fuel pump, the lower intake gasket, and last week the pitman arm. the problem i have is the darn thing hass a miss around 2k rpm. it kept throwing the random cylinder misfire or cylinder 4 misfire, so i did new plugs, wires, cap. rotor, and even a distbutor. none of that help. after that i change the injector for cylinder 4, and it still dont help...... will some body please help me!?!?!?!?!? its almost gona be winter and thats what i drive other than my 98 gmc 2wd...