03 RAM HO CUMMINS
 

Having trouble with my truck not starting when warm drive for a while shut off for a few minutes 5 or 10 get back in wont start right back up ok after sitting over night or a few hours no smoke does not run rough mileage and power ok have 157k on it any ideas thanks

Check torque on the injector supply tubes, they may be leaking when it warms up.

Try pulling the connector off the FCA when it won't start and see if that helps. They will stick and cause hard starts.

Have a cylinder contribution test and injector return flow test done to see if the injectors are in spec.

Any one of the previous 3 can cause a hard start as can other things. These are just the most common. Since you have an 03 there is a TSB for the ECU connector letting moisture in and corroding pins, might be worth checking.