Starts fine cold, won't when warm

[cobra82501]

I have a 99 7.3L that will start fine when cold, but will not restart after being driven for while. Sometimes it has to sit a few hours or even overnight before it will start. Engine cranks fine and no smoke from the exhaust which makes me think injectors are not firing. Could this be the IPR? CPS sensor was changed and PCM has been changed with no help. Any ideas?

Thanks

[firefighter317]

to see if the injectors are firing, get a scan tool and ensure the ICP sees 500 psi. sounds like you have a hp oil leak since its a hard start when hot. 6.0s have problems with the dummy plug o-rings failing n causing a hp oil leak and no start when hot so that makes me think you have a hp oil leak. when it gets hot and wont start, continue to crank (sometimes can crank for up to 30 seconds) until your oil pressure gauge comes up. if its a hp oil leak, it will usually start when you crank on it continuously for a while.