white smoke in a 7.3 would be fuel smoke , sounds to me like the copper o-ring on the bottom of one of your injectors is missing , causing major excessive fuel loss , compression going around that injector may cause your fuel readings to be slightly higher than normal at idle , you should be able to tell the engine is skipping, a cylinder contribution test should pinpoint you to the culprit injector and cylinder, by the way , anytime i have a bad running problem with no codes, its usually fuel related , you are geting u nburned fuel into the cylinder which is causin your white smoke