I have a 1989 Jimmy 4x4,4.3(v6) auto.186100km. I have had it since new so it is in good shape. But this is what I have done to try and fix it. Replace fuel pump, gas filter, new tank, new wires from GM, new plugs, map sensor, EGR value, and EGR solenoid, new coil, new TPS, cap and rotor, temp. sending unit, air filter and grounds wires, new vacuum lines.Still have the same trouble, can not afford to buy so have to fix, NEED HELP PS both of my mechanics have thrown there hands in the air and give up.