While on a longer drive last week, my car was having a really hard time maintaining the speed. It was all flat terrain and was set to 75 mph. When it would drop to 74, it would increase speed, but not by just a bit. Sometimes up to 78, 79, or 80 mph. Then it would drop down again to 74 and even 73. It would just keep hunting around in that area. I know that wasn't great for the fuel economy, but for about an hour, it was all below 25mpg. I don't know if there was something else going on that affected the fuel consumption as well as the cruise control, but that seems insanely low for uneven throttle. About 2 months ago, I changed the transaxle fluid. I topped it up until it spilled out the fill hole and it seems to have been fine up until now. I don't know it this has anything to do with it. It will be a few more days before I can get under there, but I want to check that it's still full and see if anyone has any other ideas as to what I could look at. Even now, on short freeway drives, the speed still hunts around on CC, so whatever it is, it wasn't just a fluke. Thanks everyone! Rob, 2002 Prius
