Voltage Gauge acting funny
Hello, I've gone through this forum and have read a lot about the alternators but not my exact problem. I recently bought a 96 trooper. It runs great but the alternator belt squealed a lot when started, and almost all the time if I was driving in the rain. The other day I got under it and found the alternator adjustment and got the belt tight. Perfect, no more squeal. I was driving it the day after and noticed that if I really get on the gas the gauge will drop to about 12 and then when I let off a little it goes right back to 13 plus. Not all the time though, just some times. And, it still runs great and all the accessories seem to work just fine. I did notice that on the hwy going 65 it tends to stick at about the 12 range. So, my question is what could I have done to cause this by tightening the belt?