2003 ram 2500 6 speed started smoking on the highway today and i mean smoking white just got looking at it sounds like misfiring on a cylinder pulled valve cover off none seem out of spec just checking to see if any had worked loose or something stupid put now injectors in about month ago put 5 in cause had 1 new one put in just previous before that how would i go about checking what one is not firing only thing i can figure is what the temp of exhaust on each cylinder once in a while it lets this god awful knock out then goes away please help if possible thanks jake

 

Yah, an infrared temp probe would tell you temp on each cylinder right away.