Alright my 2000 f250 wth 7.3 started smoking got worse and worse. Smoke smelled just like fuel. Checked oil just plain black diesel oil not milky or nothing. Not using any coolant. So Then we pulled the valve covers and checked plugs I read that some ppl have problems with the plugs coming loose. Everything was fine. While running started unplugging injectors. drive side was all good but passenger side 2nd and fourth cylinder did nothing. we thought it was two bad injectors or possibly valve cover gaskets so we swapped sides. and problem still existed on same side. a friend had a box of used injectors so we went through trying to find good ones. out of the whole box it seemed that there was not a good one. so we then did what we should have done way before all of this and swapped that injector with one that did bog the engine down thinking that the problem would change cylinders and it did not. So out of all that work the only thing we found out was that my injectors are not bad. With my evolution programmer it did throw codes. was getting p1316 and interuption in kapwr curcuit. Any help would be of great thanks. im stumped with the truck this is my first one and really do not know a lot about this engine. I am a mechanic but first time really dealing with these problems.