Not starting issues after engine has warmed up

Hello,

The truck starts great when it's a cold start, it does not restart quickly when the engine is hot after about 5-10 minutes of turning off the engine. I am a fan of doing things myself self but I have not been able to find the reason as to why this happens. The truck starts, it has never left me stranded but it takes longer than normal. Here is what I have done so far:

Replaced

Fuel pump and filter.
Starter.
Re-wired the ground connector (charger wire, battery ground, and engine ground).
New spark plugs with cables.

I also took the truck to a mechanic (electrician) but the truck did not make the crank and delay start when I took it so he was not able to find the problem to fix it.

what options do would you say are good for me? Please let me know, I have been struggling with this for a while.