[masraum]

Originally Posted by hcoles

Update in case people want to know....
I took it to the rebuilding guy. He knew (thought he knew) exactly what it was wrong said the brushes were worn down too far. In a few minutes replaced the regulator module with brushes. I took it back home and installed. Voltage was still not stable. Readings to 15 volts and then reads 13.1 volts.
Now he ordered a new alternator or might rebuild my old one. I'm not sure.
One thing he said... The alternator is controlled to some degree by the computer and we hope that is not the issue. I hope that is not the issue. Stay tuned.

Interesting. So he changed the VR and it's still wonky? Very interesting. I was unaware, but would not be terribly surprised if the ECU had some amount of input or control over what was going on. Still, I'd be replacing the alternator if the VR didn't do the trick.

Originally Posted by vash

voltage regulator. are they now internal to the alternators?

In most cars, they are internal and have been for a long time. There were some manufacturers that held out. I want to say maybe FoMoCo or Chrysler/Dodge had external VR for many years after most others had gone internal.

It sounds like he swapped the internal VR and is still having the same issue.