I have a 2003 6.0, innovative tunes, straight pipe, s&b intake. A few weeks ago it would not build boost until over 2000 rpm then it would start to build boost. I ran the heck out of it thought it was a stuck turbo. It cleared up the next day, then a few days later it did it again. So I ordered a new powermax and I installed it today and it is still dead with no power or boost til high rpm. Fuel pressure is good, 55-60 psi. Runs smooth no misses just no power.

 

Are you able to check for codes??

 

I checked for codes with my scangauge and it has no codes. Could it be the EBP sensor, I am not sure if the early 6.0 used them or not. I thought for sure it was the turbo, guess I have a good spare turbo now. Once I hit 2200 or so if I keep my foot in it boost builds and it makes power.