2008 f-350 knocking and smoking, new injectors

[steveyjay]

hey, i have a 2008 f-350 6.4,104,000 kms, with a sct programmer and dpf delete, it has recently started knocking and smoking large amounts of white smoke, it only does this from time to time and on a cold start,at first i was thinking injectors, but they had to be changed with the high pressure fuel pump as well with the fuel lines when a full serve station filled my truck with gasoline. i have checked my coolant level as well as my oil all is good and oil isnt contaminated with diesel. as well the rpms well flutter and it sounds like it is going to shut down when it begins knocking. it sounds similiar to the old 6.0 litres on a cold start. really not sure what could be going on here....