Pontiac Repair: Charging problem 1994 Pontiac Trans Am, voltage gauge, pontiac trans am

Question
I have a 1994 25th Anniversary Pontiac Trans Am w/only 15k miles. Just purchased it last year and drove about 1k trouble free miles. Now it has an intermittant charging problem...the voltage gauge on the dash will flutter back & forth. At idle you can hear when the alternator kicks in and out.  I pulled the alternator off & had it tested at local parts store and it charged fine. Any suggestions on what to try next?  I understand it could still be a faulty alternator, but with such low miles and the car so clean I have a hunch there could be something else going on.  Any help would be greatly appreciated!

Answer
Hi Shane:

It could indeed be a bad alternator but It should be tested on the car. That what the wiring going to the alternator is thrown into the mix and see how it works on the car. You could have an issue with a loose connection at the alternator causing the issue. How does the car run? if it has an erratic idle it will make the alternator work wierd as well. I don't belive that car has an engine control module that turns the alternator on and off I belive it's just a simple system. good luck :)