do you think that my voltage regulator is shot?

[Iceclaw]

I noticed for a while that my electical system was not 100%. For example turning the turn signal on would cause the voltage meter to jump a little.

Then some cold weather hit and as I was idling at a light on the drive home, the interior electronics started to flicker in and out. I noticed that when the car was idling, the voltage was showing very low - around 5 volts maybe, but when I was driving it would go back up to normal. So my alternator is at least partially working (and in my experience alternators either work or they don't).

As soon as I stopped the car, it would not turn over and start again.

At first I thought my battery was shot, so I put a new battery in, but the car still will not turn over with a brand new battery.

So it must be something else? Voltage regulator maybe? Help is appreciated.

[GTP Dad]

It is possible that you have a bad regulator but I would check the connections to the battery and the grounds. If it won't start with a new battery that indicates that the issues lies somewhere other than the alternator or voltage regulator. I would also check the connections at the starter solenoid as there could be an issue there.

[Ron AKA]

If cleaning the connections does not work, then it could well be your alternator. Most now have the volltage regulator internal to the alternator. It also could be that the brushes are worn in the alternator. I have seen an alternator work intermittantly when the brushes are badly worn. Sometimes they contact and at other times they do not. This condition goes quickly to not working at all.

Ron

[auto trainy]

I would check the positive terminal cable very closely, it has been known to have trouble (internal corrosion)