I have a 2000 GMC K3500 6.5 turbo. Has always ran great new ip pump no reman in September pmd relocate kit in December,new injectors in November. Has been running great then the other day went to work shut it off,went back out about 45 min later and would not start just turn over. Put in fuel pump relay and nothing, put on ip pump relay started right up. Drove around a bit everything fine, went to lunch when came back ot started up put in reverse and died would not sart back up. Went back about 20 min later and it started.Put a scanner on it and has no codes. Ran it around,started,turned off ran fine would not do it again. Drove it home, went out this mourning started it up started fine ran for about 1min died like you turned the key off. Now won't start again. Haven't been back to see if it will start. Dose anyone have any ideas of what is going on. Thanks

 

electrical?
fuel ? (fuel lines, injectors, etc)

that is were I would start to look.