Wont start when engine temp is normal

[scorpion16]

First thanks for reading. Now I have been through forums and books and still no luck. 1999 Ford F350 7.3l when the engine is cold it will start takes a few seconds than normal but starts. Replaced the Ipr Valve and still have the problem however if the truck idles in the driveway till warm it will restart, but as soon as it is drive for 5 mins or more truck will not start till cool. I have changed the oil twice, the fuel filter, the cps twice. I am all out of ideals and really need this truck running I am to transfer with my family in 9 days

UPDATE
when driving very slow acceleration. Please help really need this fixed.

[bjg8599]

check the hpop for oil?

[scorpion16]

I checked the hpop it has oil in it and I left the little bleed nut off the top and it over flows like it is filling up. thank you for trying to help.

[bjg8599]

Does it slowly overflow or spray out with high pressure? it should have lots of pressure, if you left that nut off it should have sprayed the entire engine area in just a second of cranking. if it just barely flows out then your pump is worn. these engines are actually really simple, give them oil, fuel and air and its hard to stop them, sounds like yours is not getting enough oil pressure to fire the injectors. could be other things but if you left hpop fill top off and it didn't coat you and everything around you then your pump is shot.

[Chuck stallions]

I left that plug out on my 350 oil went about 4foot in the air. So if yours is slowly running over then your hpop is shot

[rwlundberg]

yep I would say HPOP, my buddy had the same problem. His would start perfect when cold, the oil is thicker, therefore more oil pressure to fire your injectors (which use oil pressure to work and provide fuel to your cylinders). Therefore no fuel, no start. He went to the dealer, under warranty, and they installed a new HPOP. When the engine is warm the oil is thinner and the oil pressure is adequate for the injectors to fire. Hope this helps but a little insight to your problem.

[rwlundberg]

Did that help??

[a69reddog]

Had same problem with my 97. easiest way to check is unhook the high pressure oil pump line going to one of the heads and install a plug in the hose. if it starts reconnect and try the otherside. after tring both sides whatever side runs the other is the problem. remove valvecover, start and watch for oil comming from one of the injectors. that one will have a bad o-ring.