So I put a new motor in my truck and It fired right up like it's supposed on the first try, so I let it run for 30 to 40 min, then it starts running really ruff and starts popping out the exhaust but the truck still runs it doesn't shut off, I have replaced coil,distributor, alternator,fuel pump,o2 sensor, radiator.if some one has dealt with this before it would greatly be appreciated if you have advice or know what the issue is, thanks for your time hope I can get this issue figured out. Dodgeram95

 

You most likely need the fuel sync set.The computer handles the timing. The fuel sync is set with the distributor. There is a notch in the housing to align the rotor for a rough setting. Then adjust while hooked to a scanner.

 

https://dodgeforum.com/forum/3rd-gen...correctly.html

Here's a link

 

And here's a pic...