2005 6.0 F350 starts up but IPR goes directly to 95%. Truck will run and idle but it's a rough idle. When driving at lower RPMs it will sputter at a couple of different RPMs and run fine above the 2000 RPM Mark. When hitting 1700rpm or 1300rpm it starts to sputter until I feather the pedal. Changed out the IPR and still does the same. Any thoughts?