And only on a cold start, first thing in the morning. After the truck has warmed up it has no further trouble. If I let it run for about a minute after starting, it's also fine. It's probably just a coincidence, but this started right after I changed out my original battery. Anybody else have a similar issue and learn how to fix it? I don't get a CEL by the way.

 

Well, I found the problem, and boy, do I feel like a dope. When I changed the battery, I was a "little" overzealous with the red spray terminal protector gunk. In fact, I sprayed the terminals BEFORE I reattached the battery cables, thinking that if I twisted them as I worked them into place, it would displace the red gunk wherever I was making tight contact, leaving a good film on the parts of the terminal where I wasn't. That don't work quite the way I envisioned. Just for grins, I pulled the cables off, and discovered I still had absolutely great coverage on both terminals. All of both terminals, LOL! A little while later after some rather delicate sandpaper treatment, I reattached again, and this time I only sprayed after tightening to spec. Worlds of difference. I'm probably pretty darned lucky nothing burned out.