I decided to upgrade my fuel system and I installed the FASS titanium series 100GPH system and also a Fleece fule filter bypass. The truck ran fine and I filled the tank up. The next day I took the truck for a drive and I got code P0251(injection pump fuel valve feedback). I cleared the code with my edge CTS. I started the truck and immediately had code P0148(fuel delivery error). Turned the truck off and cleared the code, restarted and I had both codes return. I called FASS tech support this morning and they say they have never heard of this happening. They think I might have had problems and now with good fuel flow it is causing problems. They did tell me to add a pressure gauge at the FASS pump and make sure it is putting out 16-18 PSI. I verified with a gauge and the FASS pump is at 16psi. I ordered and replaced the following- new bosch fuel control actuator, new rail pressure sensor and rail relief valve. I am still getting both codes P0251(injection pump fuel valve feedback) and P0148(fuel delivery error). The truck idles fine but I have not tried to drive it as I don't want to cause any damage. My next step is to add hose clamps to all the push lock fitting on the FASS system, check torque on fuel lines (just to make sure I am not sucking air anywhere). I am trying to find my fittings so I can do a flow test on the CP3. I can't think of anything else to check and now I am leaning towards a CP3 replacement. I really need to fix this as my smog and registration is due in a week. Any help or ideas is appreciated.