94 Regal Custom Electrical?

Maybe nothing, but twice in the last week, while sitting at a red light, the car acted like it was going to stall. I did notice the voltmeter head for zero, idle became rough, lights dim and then recover in a second. The alternator is new and has been rechecked at autozone. I have been to all the grounds that I could find under the hood. Is this indicative of some future failure? Engine is a 3.8L (100K miles) with new plugs, wires, alternator and serp. belt.

Thanks,

What about your battery and cables/ connections?

I have had them off, clean and tight, grounds too. I have heard that battery cables can be a problem with these cars. Is there a way to test them other than continuity?