Long time listener, first time caller. I have a 2007 3500 with a 5.9 6sp, 50k on a rebuild with ddp 40% overs, fass 165, arp studs, Hamilton 182/214 cam, stock turbo, efi live. The other night it was driving normal, then out of nowhere it felt like I lost the turbo. Giant clouds of smoke and had a really hard time picking up speed from 3rd gear on. Got home and pulled intake, turbo shaft feels normal, boots are all tight. Plugged in auto cal, have a p0191 and a p0148 code, so I am thinking it is just way over fueling, not lacking boost, which made sense to me because it ran ok on the top end. I replaced the FCA with no change. I'm going to try the rail pressure sensor next, but wanted another opinion before I keep trowing money at it. It starts fine and idles/ runs through 1st and second gear fine. I tried unplugging the pressure sensor at idle and it started sounding like a 12 valve, so I'm really not sure what it needs.