I had my 1999 5.9 Durango shut down on me a couple of times after its been running for a little while.....took it to a trusted mechanic and luckily it shut down while I was there so they could check it out, since it hadnt thrown any codes
Diagnosis.....no fuel pressure....they put in new fuel pump @ almost $500, same problem still....they replace it with another fuel pump the next day.....same problem.......I have now spent $500 and still dont know what the problem is...........they now tell me that it may be my computer, that has to be done at Dodge.......they say they replaced the relay at the same time, so that shouldnt be the problem............any ideas, and how much does a computer for a D cost?

 

Couldn't tell you the cost but it definitely sounds like your PCM is fried. You could probably try to get one out of a wrecked 360 Durango and swap it in.

 

sounds like your IAC needs cleaning or changing. It's on the backside of your TB. Hope that helps