So I was driving the other day and the engine just cut off. The lights, radio and all the electrical in the cab all stayed on. Tried to jump it and that didnt work so I towed it home. Checked the battery and alternator both were good. Checked to make sure the motor wasnt seized up and its not. Replaced the spark plugs and wires (pretty sure the old ones were the originals on a 200,000 mile truck). Checked to make sure I was getting spark to the plugs and I am. Then I went to fuel. Checked the fuel pressure and it was really low around 15psi. I replaced the fuel filter. Was still getting low pressure so I checked the fuel pump. Turns out it running weak so I replaced it. Pressure is now up at 65psi when the key is turned. Spec is 56-72psi So I have both spark and fuel at the engine but it still wont start. any ideas on what it could be?