jwh34761

So I'm having an issue with my truck. I can start the truck and go drive or just let it idle for a period of time, then turn it off and back on and it really hesitates to stay running. The RPM will stay below 1000 and fluctuates from near 0 to 1000. Its a 50/50 chance if it corrects itself and runs normal or stalls out. if it stalls out its even a less chance that it will start again. If i let it sit for around 45minutes to an hour it starts up fine no issue. it is throwing a P0171/p0174 code. I have replaced the coil pack,spark plugs,MAF sensor,O2 sensors,EGR Valve,EGR valve pressure sensor, EGR vacuum solenoid, and its been to the shop to fix all of the vacuum leaks. I'm running out of ideas on what it could be, i plan on possibly replacing the fuel pump, the pump relay, and fuel filter. tonight is when all the EGR parts and spark plugs were replaced, and I'm not sure if its been doing it the whole time or not but after i put the new parts in tonight i took it for a test drive which felt like it had improved in some way but after returning home and letting it sit for 10 minutes, i tried to restart it but this time all the lights and power were flickering(its dark outside so it was more noticeable). it did stay running but threw the same two codes as soon as it started. the power flickering may be a total different issue as my battery may be going bad, but i'm at a loss and would appreciate any input given.