17 JANUARY 2014, 20:44 There's a service plaza on the Indiana Turnpike that sells dark chocolate mochas.

It's the one just over the border from Ohio, if you happen to be going in that direction someday. The, um, snack bar is run by, I think, the South Bend Chocolate Company. And they make their chocolate drinks with chocolate. As in, melt the chocolate and pour it it the milk. Oh, my.

This is a nice thing to contemplate, especially in truly cold weather. Which has suddenly come upon me. This morning it was barely below freezing in Pennsylvania. At lunchtime it was a fairly comfortable forty-something in Ohio. Then I hit a wall of snow as the temperature dropped ten degrees in an hour.

That actually wasn't too bad, except for the cars disappearing in front of me. I don't like following invisible cars. I'm never sure they won't reappear, much closer. And nobody else wants to slow down.

Oh, well. Eventually things cleared up, and we all tooled along happily again. For about another hour. Then it started snowing again. And the temperature dropped another ten degrees.

And things stated getting weird.

The first hint that this was no longer a normal day was when the engine started to overheat. In a snowstorm. At twenty degrees Fahrenheit. Fortunately, I'd run into thiis before, though. So I pulled over at the next service plaza, climbed out of the truck with a walking stick, and started pounding on the grille.

A couple of minutes worth of gratuitous violence, and the ice that was keeping the air away from the radiator was mostly gone. So I climbed back into the truck and headed on down the road, admiring the new and more reasonable temperature readings.

At the next service plaza I stopped again, this time to knock the ice off the windshield wipers. When I started again, I noticed a new odd thing.

The engine wouldn't rev up all the way.

The engine in this truck has a redline around 1900 rpm. You usually shift somewhere around 1700. Suddenly it decided anything over 1500 was just Not the Thing. No stumbling, no roughness, no hint of mechanical problems. It just spun up to 1500 rpm and stayed there.

Fortunately, 1500 is enough to let you shift. Barely. And like I said, it ran like a sewing machine otherwise. I suspect something happened to the engine computer. Maybe something to do with the governor.

In any case, it made a nice excuse to shut down a little early. Hopefully sitting all night will give the engine computer a chance to reset. Hopefully that will get the engine back to normal.

And meanwhile, I get a dark chocolate mocha.

And a good night's sleep. Sweet dreams.