Raw fuel and gray smoke coming out the exhaust

I forgot to add..the oil level shows a half quart low and hasn't change since we been working on it so there is not much fuel getting in the crankcase. Also # 4 cylinder is getting good compression. We are getting 2.4 to 3 volts to #8 6 4 but # 2 we are getting 14 volts when truck is running. Leaning more to computer problem. If anyone has A better idea than me, please let me know.. Thanks

If plug was soaked that tends to make me think that for some reason it was not firing or was getting to much fuel. I might would try a another plug and see what happens. Then try swapping the #4 injector with another one and see if the problem follows the injector or stays at the #4 cylinder. If it follows the injector replace the injector. If stays at #4 cylinder double check plug, plug wire and injector pulse.

Thanks for the help dandy... Yes we tried all of what you suggested earlier before I posted the problem and still had lots of grey smoke and raw fuel. The problem didn't follow the injector. We replaced the brain box and check voltage to the #2 cylinder and we are getting 3,8 with the truck running. Plug the injector connection back on the fuel rail and fired up the truck and no gray smoke or raw fuel. Check engine light even went away.. Thought we might have to flash the used brain box we installed but so far no strange codes have showed up.