'94 Cherokee, 4.0 doesn't always charge like/when it should. Maybe one third of the time it will start charging immediately when I start it up, just like it should. But most of the time I have to drive it for a few (2-5) miles before the needle comes up. I have discovered that I can force it to start charging by revving the engine pretty high... I don't like to do that but have needed to a couple of times as the battery was getting low and things were starting not to work right (after twenty miles or so with lights on). After the charging process is initiated I have no further problems until the next starting. It seems the regulator must be sticking or something similar but I do not know where to start. Thanks
Matt