2006 ISX CM870 High Pyro, surging under load

[sickoftrucks]

There is no delete programming, the truck to my knowledge is 100% stock. Basically, the two problems are the high pyrometer temperatures and the surging. As i mentioned before, the fuel is black as can be, i am having it tested now. I suspect the injectors are causing over fueling, and the over fueling is causing the ECM to cut back the fuel due to high exhaust temp readings. we need to run the test where the engine runs on one cylinder at a time before anything else. Turbo controller has not been changed. i watched some of your videos on testing the injectors. I need to see what we get for results before moving on. Thanks