Drue,
Your description of final results was not completely clear. Did you say that after many tries the engine ultimately started, ran rough, then smoothed out and ran normally? Will it start and run normally now?
Did you recently fill the fuel tank shortly before the start/run problem began? If so, I would pump the fuel out assuming you could have purchased a tank of bad fuel. I recommend pulling a fuel sample from the tank and having it examined for water or other contamination.
What did you mean about water in "it" during a rain? Did you get rain water contamination in the tank in quantity?
Pull the top off the fuel filter cannister and cycle the key to see if the fuel transfer pump is pumping adequate fuel supply.
Would it be possible to borrow a known good FCA from a friend or fellow TDR member to install briefly to prove or eliminate the FCA as a cause? It is quick and easy to remove and replace.
I doubt an injector problem. I put 220k miles on an '06 in a short time. It ran as good the day I sold it as the day I bought it on original OEM injectors. No doubt they were worn some but not malfunctioning.
I'm not a mechanic but if I'm understanding your report(s) it sounds like a problem that is common to all six injectors not just one.
It was many start attempts at cranking, I cannot remember how many times, not enough to run down my new batteries(<3 mo old). I never noticed the cranking speed slowing or I would have hooked up jumper cables or battery charger. Since that incident, I have put over 2500 miles on both highway with and without heavy load and truck has performed flawlessly. I cannot detect any issue.
The first 150 miles of that tank were cruising down the interstate with empty flatbed(~5000lb), the other 150 miles were running around town empty(light load). So I had put fuel in on July 5 (a full week before problem). I still had ~3/8 tank remaining. After I did get it to run properly, I did go top off with fresh fuel from a normal source that has had good fuel in the past on the Interstate. I trust this station because I know they move a lot of fuel and are a major supplier to other stations. I have filled up at least six more times since then and no issues at all.
The rain issue was in the catch pan under the truck from the fuel flow test after filter was replaced. Pan was left under the truck when we had an afternoon thunder shower that had gusty winds and about 1. 25 inches of rain fell in a 45 minute period of time. Some of this rain blew under the truck and contaminated the drained fuel about 4-5 hours after I checked for fuel volume flow. The fuel in this plastic pan showed no signs of water bubbles or sediment of any kind. I looked very close at this fuel prior to the rain storm. I wish I had captured a small quantity in a glass jar for analysis, but that is behind me now. But the fuel in the tank has never had rain in it to my knowledge. I am sure it has had water from my fuel sources and from natural condensation, but if the problem was indeed water in the fuel, this is my first experience with this truck. I have experienced water in fuel many times with farm tractors and older diesel engines, just not this truck.
But I do agree the problem sounds like a problem that is common to all six injectors not just one. I think the problem is upstream from the injectors, but downstream from the tank. I still question electrical (probably because I don't understand everything that could be happening) issues. I know the basics of what is happening, it's just those little details that are fuzzy in the wires and black boxes.
SO for now I am still going to conclude root cause = BAD Fuel. Problem solved through time. I do not want to throw parts at it trying to make the problem disappear when it is already gone.
I do want to thank everyone for your 2 cents worth. It really does help to bat different ideas around. Many thanks, Drue
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