Voltage meter surging.

[ca1a73]

My aftermarket voltage meter is moving back and forth between 12-14v very fast. Is it my alternator? I never had the problem until I undid some of my dash to install defrost ducts? Loose connection somewhere? Voltage regulator? Can someone please help? Where do i start? suggestions?

 

[RRRAAAYYY2]

I would think you have a loose connection somewhere, most likely the ground got messed up.

 

[ca1a73]

The ground to the voltage guage itself? Another problem I noticed, is that my lights get brighter when I step on the gas. Is that my alternator?

 

[RRRAAAYYY2]

If these both started happening at the same time, I would now look at the alternator first. Sounds like it has had it. Either that or you have a really low idle. But if the guage is bouncing even when you are driving, then most likely you have burned a phase out of the stator.
Get the alternator off and have it tested.

 

[Bart]

I had/have the same problem. I also had alternator bearings going so I replaced the alternator and the "AMP" meter keeps swinging, the lights are also flucuating too. I'm guessing there might be a ground missing between the body, the engine and the battery. I know the alternator/engine block to battery has a good ground but not sure about the body or maybe even the dash ground.

 

[RRRAAAYYY2]

Here is the proper way to check for bad wiring:
http://www.svapowerproducts.com/html/voltage_drop.html

If all your wiring is good on the ground side. Check the wiring to and from the regulator as well. My next thought would be a faulty regulator. It can be removed and tested at your local rebuilder. Just remember to unplug it while the regulator is still attached to the firewall/fender. And when reinstalling it, absolutely make sure you mount it firmly in place before plugging it in. Or you will damage it, more likely blow it up.