What happened - need counsel #2

[CKHeller]

I went to the dealer to pick up my truck. The service manager said it would be hard to start and blow out gobs of blue/black smoke. It started right up with no more smoke than usual and ran fine about half way home, thats about 7 miles. Then it started to stumble and blow out clouds of white smoke as I stomped the gas and kept it in gear. This is the same thing that happened to my wife the other day when she had it towed to the Dodge dealer, see yesterday's post of the same title. After a few seconds it would catch, accelerate for a while then start to stumble and I went through that same cycle with increasing frequency as I drove. It also had more difficulty getting itself running again each cycle until I was about a half mile from home and it stopped completely and would not start. I hope after a cooling off period it will start again and get it home.
It doesn't seem to me that the dealer replacing the FSS changed anything. That diagnosis by the dealer didn't make sense to me any way: Correct me if I'm wrong but it seems to me; the FSS would not cut off the fuel if the ignition switch was in the on position and make the truck stumble while running. It may be starved for fuel but not for that reason. Water in the line doesn't make a lot of sense either because it runs fine for a period of time, maybe until it reaches a certain temperature. Water in the line was suggested by a couple of guys last night. I think water an unlikely cause because I had no problem with the first 3/4 of that tank and I get fuel at a very active diesel truck stop and again the tank is now just below 1/4 tank and with the first 3/4 it ran fine. The problem started before we had the freezing weather overnight that should rule out condensation.
Oops! I thought I'd sent this and went out with my old Power Wagon to pull it back if necessary but was able with great difficulty to get it started and with billowing clouds of white smoke and 4 complete stalls in just under a mile to get it up my long driveway next to my garage.
Vaughn - I wasn't able to get a bottle under the fuel filter/separator to check for foaming. My filter does not have one of those long tubes the diagram you included yesterday and there is no room without removing something I'm not sure what is or does to get anything under there. I couldn't find any leakage around the fuel heater anywhere.
I used the ignition to run the codes to see if that told me anything. I'd never done that except once months ago and that time it gave me double 5's. This time it was difficult to read I think because I'm unfamiliar with what is a pause. At first I thought I got 35 but there is no 35 in the Haynes. Once I thought I got a 12 and a 23. The 12 makes sense because the batteries are new. The 23 also says the check engine light will light when the engine is running so I tired to start it just for sport and to my total surprise it started and ran fine for several minutes. Does this truck have a ghost? Anyway the check engine light didn't come on while it ran.
Does this make sense to anybody? It's too late now and I've used all the energy I have for today getting this much done but maybe for tomorrow someone can give me some clues about what to check next.

Kru Heller
Powhatan, Va.
94, 2500, 5 sp, 4 WD, reg cab, long bed