05 F 250 Harley Davidson diesel 6.0
 

I'm having a start problem the first time for the day it starts good runs good it just takes 10 seconds or so. The rest of the day it'll start fine 3 to 4 seconds to start. It's only hard to start after it sits about 15 hours. I've had gauges on it the high pressure oil bleeds down overnight or roughly 12 to 15 hours. You can watch it build pressure when you start cranking it and when it reaches pressure it starts the rest of the day it holds pressure. It starts in 3 to 4 seconds and it always starts strong and never has a hard time starting hot or cold just can't figure it out. I have Inavative programming PowerMax turbo 190 injectors head studs EGR delete innovative fuel system aftermarket FICM. I have replaced the high pressure oil pump the timing cover and gears. does anyone have any ideas please help. The truck runs great otherwise. Thanks.

Do u have motorcraft filter and stock cap for oil? Sounds silly but some are too short and don't seal the drain in bottom of oil filter housing.

Yes I do thanks.