I randomly get P0148 fuel delivery code and P0191 fuel rail pressure. I have seen this code off and on for about 2 or 3 years now with no performance problems. Every once in ahwile I have a miss is the best way i can describe it. It feels like a gas motor with a spark plug or a coil pack going out, but it is like having a single misfire versus several before they go out. Yesterday I got both codes and my truck fell on its face and would not even accelerate to go on a flat road. It just kept decelerating and eventually started slowly picking back up on speed. After I stopped at a gas station and restarted the truck it hasn't done the same thing since then. The two things I find are potentially the fuel rail pressure sensor and the fuel control valve. I have noticed that I am blowing more black smoke on acceleration lately on lower settings than I used to. I have an edge juice with attitude. It used to clear up once the turbo spooled up, but it takes a lot longer for it to clear up if it does now. Which part should I start with changing first? The codes went away today and it is running fine. I recently changed the oil, fuel filter and got a new AFE air filter about 5K miles ago.