My gauge will read a random drop in voltage causing my lights to dim and the car to hesitate for a moment, is this something with ignition or more like a bad battery issue? I drive a 91 camaro z28 that has low miles.

Thanks

 

First check the battery. Try moving the connections to see if they are loose or dirty.

Second Auto Zones or similar stores offer on vehicle testing of the battery and alternator. I would start there.

 

Does it only happen at idle or when driving too? What is the engine temp and idle RPM? Try to figure out if it happens totally random of if its when the fans turn on or AC compressor or at certain temps. If the idle is set too low I've seen some cars almost stall when the AC compressor turns on or the voltage drops excessively when the electric fan turns on.
My 91 would idle too low when I first got it, and stumble occasionally when idling for a long time at a stop light. I cleaned and adjusted the IAC and it got better but still would occasionally idle too low. I eventually replaced the IAC and now it runs great. If your problem happens at idle you may want to look at the IAC, the little stepper motor inside is very sensitive to any kind of dirt or debris.