Does the voltage pick up a bit with higher RPMs? I had a similar problem when I first got my car. At idle, the voltage would drop to the point where the battery light would start to come on. I replaced the battery twice (first replacement had a weak cell) and eventually, it just wouldn't start. I was getting proper voltages everywhere and was starting to suspect the coil. Eventually, I checked all the fuses and found all of them oxidized and two with burn marks and starting to distort. I replaced all the fuses and cleaned up the fuse block. It started right up and I haven't had any electrical problems since. Jim #11544