Ok guys. Im in need of some advice/direction. Im mechanically inclined and im sure i can fix any mechanical issues that need to be done.

That being said...

2006 dodge ram 5.7 hemi crew 4by4 sport. Driving on highway at 100kph. Engine running one second, dead the next. No loud noise, no excitement. Just on, then not. Engine turns over. Fires the odd time but never more then a single attempt. Wont run. Turns over fast enough. (Battery and starter only a few months old) NO CODES. fuel pump sounds fine. Plugs look good. Its had regular maintenance
Taken care of, but works hard when in use. It has 199,643 km.

I know what i think is likely wrong but i am looking for more opinions. What should i look into doing next?

Check fuel pressure. Sounds good, doesn't tell you if the pump is working. It just tells you the pump runs. Its possible a head gasket or valve spring let go. Just my opinion I would do a fuel pressure check. If that's good do a compression check.

Ok. Is the 5.7 a non interferance engine? Or can the valves hit the pistons if the timing chain broke or skipped a few?

Very rare for new engines the skip time. It takes alot to break a chain. If I were a betting man I say fuel pump. I would do a pressure check to verify.

What about the crank sensor? That would result in spotty firing, and a no run situation. Pressure test the rails first though.

Testing the pressure today. But, wouldnt the fuel pump or the crank sensor throw a code?

Not always.

Fuel pump would not.

Ok. Fuel pressure is 53psi. Pump is working fine. I am getting spark. How do i test the CPS?

So. Still wont start. I have fuel and fuel pressure. I have spark. I have 130plus compression in 1-8 so the valevs are opening and closing. I changed the crank sensor. Still no codes. Something electronic must be messing with timing??? I am wondering how to test the computer? What should i be testing next? Or is it at the point of going to dealership???