Well here is what the car is doing. It runs a little rough and sometimes wants to cut off. The voltage gauge in the dash bounce between the higher numbers. The head lights and dash lights surge bright to dim. So I did what you would normally do, since it's a new alternator, check and clean all the ground locations. Well that did not effect it at all. So I started to wonder if it was the alternator itself. I then unplugged the alternator wire feeding the gauge, or so i thought. The plug that goes into the wiring harness, is the one I am referring to (the only plug on it anyway). I then noticed that the cars idle cleaned up and the headlights didn't flicker anymore. So does that lone wire just feed the gauge or does it send a signal to the computer to monitor voltage?

 

The small wire to the alternator does go to the electronics in the instrument cluster, but without it connected, the alternator will not charge at all (not function). It is the "exciter" wire that tells the alternator to turn on.

 

So what would cause the system to act like it is? bad alternator? I took it off to get it tested tomorrow. Hopefully thats what it is, if not I will be stumped.

 

the exciter was aching and had gotten fried. just for search purposes. she said we could get rid of the exciter and make it charge all the time. then wire in a aftermarket gauge but i decided just to get the exciter replaced. next time she is going to set up a smaller alternator for me, so it will clear my valve covers and not have to grind on it.

 

you chose the right path if you removed the exiter and the alternator was charging all the time you would cook your battery which can be dangerous.

 

I would be curious to know what model number that smaller Alternator is, to work with our charging systems, so I could get one also and change my valve covers?? (It would have to be a 140 amp Alt)

 

call advance or somone and ask about the alternators for the impala ss. there will be 2 listed , 1 is smaller than the other. i know its not a 140 amp though, its slightly lower. you will have to turn the face around and do 1 other thing ,can't remember what she said though. see if you can find a local place that rebuilds alternators , and ask them to set it up.