Well as many of you probably know, I've been having an ongoing battle with my voltage. When I stop at a light.....it goes down...and when I accelerate it goes up to normal.

So yesterday my friend and I were driving to play hockey and I notice that my voltage is just chillin at about 11. It's not moving, even if I accelarate. So I'm thinking, no big deal!!! Then the b*tch starts decreasing. So by the time we got there....My voltage was almost in the red zone and for some reason my AirBag light was on. Just as I was pulling into the parking lot, my car stalled. I could not get it started on it's own so I had a buddy come jump me.....The voltage would stay at around 11 and as soon as he took the cables off it decreased and stalled. So a buddy came, we took off the alternator, and drove to autozone. They tested it and said it was 100% fine.

We put it back in and started looking for wiring issues......and after sooo much frustration, we realized that the gray wire connecting to the back of the alternator (with a nut) was disconnected on the other end. Now I originally had the other end of that wire grounded on a bolt designed for it near my headlights. On that same bolt, my + battery was grounded as well. I guess it's stock?

So my friends dad suggests that we connect the other end of it to the actual + battery post. So I did it and my car started. It's now back to the way it was (low volts at idle, and going to normal after accelerating).

My question is...Could this gray wire be too small of a gauge? It seems to be about 11 or 12 gauge. Also, if connecting it to the battery post is a bad idea? I'm thinking of I get a bigger size it might help my volts. Any suggestions would be greatly appreciated!!!!! Thanks!

 

91 should have a CS series alt, typically in a TG it will use 3 wires. 2 going to a plug at the top and one from the rear of the housing with a nut, that's the alt output wire. Thats the one that carries the voltage to run the car and maintain the battery. In almost all stock applications it's a heavy guage red wire, use a minimum of a 10 AWG wire if replacing it. That ground you talk about where they tied together is NOT a ground, it's a junction block that is insulated from ground and used as a tie point. From that block there is a fusible link between it and the battery. If you hook the wire from the back of the alt to the battery positive directly and it starts to charge most likely the fuse link is blown or there is a wiring problem. If you have a voltmeter disconnect both battery terminals and the wire from the back of the alt and measure using the ohms scale from the wire off the alt to the positive battery cable-it should read zero ohms. Or, in lieu of a meter use a self powered test light and hook one end to the loose positive battery cable and the other to the wire from the back of the alt. the test light should glow at full brilliance just the same as if you would hook the test light wires together. Any difference in brilliance indicates resistance, find the problem and correct it. Thats why I prefer a meter, but I realize many people don't have access to a decent DVM. You get extra green it's a good investment, especially if you own a TG. Never jump that wire from the back of the alt to the battery for anything other than testing leaving out the fusible link, it's a recipe for disaster if a wire chafes or a problem with the alt develops. Let me know how you make out.