I have a 2001 Ram 2500 with a 360
it runs great most of the time, but will just shutdown randomly, then it might take 5 min and it will fire back up
the other day when it did it, showed no bus for maybe 5 seconds , went away and fired back up.
I have replaced
distributor cap and rotor
coil
crank case sensor
unplugged every connection, cleaned and checked.
Any suggestions would be awesome, chasing a ghost

 

I had the same exact problem with mine. Took me MONTHS to finally track it down. I had a combo of some bad ground wires, broken wires (including some grounds) within the harness above the engine and a bad speed sensor/ speed sensor wiring. The speed sensor threw me off a bit, but if you look at a schematic, it is pretty interconnected to many other sensors within the PCM. Hope this helps, best of luck.

 

A "no buss" is usually a communication problem with the pcm. Do a search for no buss there are plenty of post's on it.