Well, I got her home, and let's just say the start to my adventure was an adventure! This is gonna be a long one, and TLDRs are for Reddit.
Best laid plans being what they are, we started out first light of day, had a pretty uneventful drive to CO, getting to the bus around 12:30MST.
Though the dealer wasn't there (it being Saturday), the bus was plugged in and warmed up and started fine. We immediately got on the road and I was psyched as it seems like the engine was more powerful than I was expecting, pushing to the limited RPM/speed very easily and holding her own at 65 on the slight grades out of Monument, CO.
About 90 min in (on a relatively flat bit), I felt an odd behavior in the engine, which I still struggle to describe accurately. It doesn't feel like the throttle is cut off (like I took my foot off the gas) it almost feels like I imagine an engine brake would, a slight pulling back, very quick and jerky. I write it up to new bus jitters and my relative lack of familiarity with diesels, and especially THIS diesel. There is also a definite whine noise (sounds like the turbo winding down unexpectedly) associated with it. About 5 minutes later it does it again, then again, and again and again with increasing frequency. Then I hit my first real hill and it starts doing the above referenced cutting in and out thing about every second and the engine starts to feel really rough and shaky.
So I pull off, pow-wow with the wife, have her call Good Sam to make sure we got our failsafe in place; they give us the thumbs up, and we decide to push further ahead hoping maybe it is just old gas or a bit of crud that just needs to work it's way out of the system after having sat for months. No such luck, I hit a couple more substantial hills, and now I'm down to 35 or less with a very rattly engine that is cutting in and out pretty substantially.
I pull off again, resigned to a tow to a shop to leave the bus in CO for a while (none are open) and start making phone calls. First to Good Sam, where they kindly inform me that the policy that we bought to cover the initial transport will not cover any of their services. My wife tells them how she explained the situation about us picking up the bus on this trip and the agent understood and said it was covered. A supervisor goes back, listens to the original sales conversation, and tells us that in her "opinion", the salesperson didn't understand my wife, and that she wasn't clear enough, and so we're up $#!+ creek, "sorry, we can refer you to a towing company." I won't bore you with the details of my rage, but Good Sam left us stranded on the side of the road faster than they took our initial money (which they never offered to refund either), needless to say, I am vigorously not recommending them their services anymore.
I track down a mobile mechanic and explain the situation. We decide I will try and limp back to Pueblo where he can take a look. So I drive back 36 miles to Pueblo. The bus has sat for an hour or so during this period and cooled off (it being in the 30s outside). On the drive back it actually handles fairly well, the intermittent power thing not exhibiting itself at all, of course there were no substantial hills on the way back.
I park the bus in a parking lot, the mechanic comes out, looks everything over, and says he's not sure what this issue is. The engine and transmission didn't throw a code, and the engine sounds fine at idle. He says it might be bad o-rings in the fuel injectors, but that's not something he can fix in an hour on the side of the road. All fluids are good, the air filter is a little dirty, so he pulls the external one and says to drive home on just the internal, and that he doesn't think I'll do anything that will actually damage the engine with the behavior that I described if I just try and power though.
I'm wary, but I don't have a lot of good options at this point, so we decide to go ahead with the trip, fingers crossed we don't do any lasting damage. We drive on. Every substantial hill is awful.... shuddering, intermittent power, speeds as low as 20mph. The pass going through La Veta is pretty grim and I start second guessing my decision as it sounds like the engine is just going to drop out of the beast, but we make it though, and that is the worst if it.
She actually handles reasonably well as long as I'm not going up a serious hill, though it does occasionally do the power thing on flats, and many hours later we pull her in front of the house at 2AM, I'm sure my neighbors appreciated the backup beeps.
So, I got her home. At this point, it's not a quick drive to the nearest mechanic, and part of this whole thing was for me to figure out how to work on this engine myself, so I'm going to google a bit about what that issue may be, any ideas on where to start debugging from the more experienced mechanics here?
Incidentally, I also hit a pole at a gas station and bent my light housings on one side, and when jumping a curb at home, I seem to have damaged an air line (as the low air pressure indicator kicked on, and now the system has issues staying at pressure). Those things are pretty trivial in light of the engine issue though.
What a day! We knew this was going to be the start of a great adventure and our first hours with the bus did not disappoint!
