Yesterday after work I stopped to fill up and everything was running fine. After filling up I got on the highway and was coming up to speed when my truck(99 24 valve) started missing,losing speed and had a lot of white smoke coming from the exhaust. I pulled over and it would hardly idle and it smoothed out and I got back on the highway and drove 70 all the way home. This morning I got in to go to work and its the same symptoms all over. I havent been home to check it out but wondered if it could be fuel related.Thanks.

 

Exact same thing happened to me( my thread is about two threads above yours) I Changed injectors yesterday and runs better but still rough idle and white smoke, not as bad as before but still there. Tonight im going to change my fuel filter which i should have done first I suggest you change your filter and see if that helps any. Drain your water/fuel separator and see what it looks like and keep us updated

 

White smoke with a miss is unburnt fuel.

 

Either you have an injector giving you grief or your pump can't time right anymore.

Check fuel pressure going into the injection pump.
Check for codes.
Start reading this too
Mopar1973Man's Dodge Cummins Articles - 2nd Generation 24 Valve

 

Injector, Head Gasket, Injection Pump, Timing with Injection pump

 

Mine did this as well turned out to be my vp44
check your codes with a scanner if u get the 216 code u need an injection pump
Hope that's not the case good luck

 

I had these same symptoms with my '01, and it turned out to be a bad lift pump. After the lift pump was replaced, my truck ran like new, and all the previous mentioned symptoms you described went away.

 

Here's a definitive 98.5-02 fueling diag guide:

http://stuff.is-a-geek.net/OnlineDoc...diagnostic.pdf