Kent,
We just moved from Seattle to Colorado. 6200+ altitude. My 1983 300d accelerates very slowly from a stop, but once it is going about 15-20mph, it seems to perform just fine and cruises at highway speed very well. It has been a little slow to start and once and a while idles rough at the start. On my trip here, on some mountain passes, I had it to the floor, but it still could go 70-80mph up the mountain.
So, what would be the order of steps you would recommend to improve this situation? I just got it and have not purged, adjusted valves, or anything yet.
Thanks!
jared