Ok 04 Lb7 mods in sig. Few days ago started it up and after about 10 min of idle in started sounding like a powerjoke. Got P0088-89-90 codes and 1940 rpm limiter. I always run diesel kleen and fuel filter is 3k old. Well I logged it with Efi and cts. Desired rail psi is normal but actual is 25-26k no matter what. I figured stuck open fpr. Is there a way to take apart and clean it or just buy a new one? Gonna tear apart in a few days just looking for some insight. Thx guys.