I have a 02 lb7 6.6l 2500hd. It has a banks six gun tuner and an Air dog raptor lift pump. I just bought the truck and it ran fine but now it's messing up. The truck will idle it takes a few cranks to get it started. If I try to drive down the road the truck will start to lose rpms and then eventually die. But will start back up, when it first did this I tried to prime it and when I turned the bleed screw before I started pushing the primer button all I heard was air escaping. I would push the primer and after a few pumps fuel would come out and the truck would start right up but as soon as I started driving the truck would die. Fml I don't know what to do

 

what are your rail pressures, I am an amateur, but have had to replace injectors for the 2nd time at 200k. Two of them were clearly black and dumping fuel, I had not looked at the balance, Maybe I only needed to by 2 injectors if i had a tool that would read the balance (what tool did you use to read the balance?). Also, when was the last filter change?