The Cummins Mobile tech hooked up back at the engine. Did a turbo load test, engine diagnostic test said performance of all cylinders was SAT, Injectors were SAT, no codes showed up. The 1st mechanic found a ASB sensor code and I got that dash light but it went away. I did flip the exhaust brake switch back and forth it did not have an effect.
Right now I am leaning towards the gas pedal but at 600 bucks I'm looking for a way to test it.
I forgot to say this is a 400 - ISL my boost is normal when I get up to speed. 27 or so