I few days ago my volt gauge started tripping out. It would go anywhere from 10 v to 16v, spasticlly. Now it won't come off of 10v. The battery is new and I had the alternator rebuilt about a year ago. Do you guys think its the alternator again or maybe a voltage regulator?
The back of the alternator still magnetizes a screwdriver while running, so I know it's running but to what extent im not sure. I'm thinking it's just holding on enough to pull 10v.

Any ideas would greatly appreciated.

Thanks

 

If the volts drop that low it is the alternator. This happened to my car twice everytime the volts go low the alt was shot.

 

I only trust the dash volt meter until it shows a problem. The best thing to do is put a multimeter/volt meter accross the battery terminals whilst the engine is running, and read the output that way. Get a buddy to rev the engine too, to see if it changes the reading. Anything below 13.5v or above 15.5v is an alternator problem. Ideally you want it at about 14.5v steady.

Si