Can bad electrical in car audio cause subwoofers to bottom out and not produce much bass?

I have 2 10” PSI baseline subwoofers (rated at 750rms each). They are wired to 2ohms. I also have a Hifonics BRX2016.1d (rated at 1400rms at 2ohms) in a 1990 vehicle. Compared to my last setup (that was a lot less power) which was 2 10” off brand subwoofers rated at 250rms each on a 300rms at 2ohm amp, it’s not much better and I am stumped as to why. One thing I noticed with my last setup compared to my new setup is that with the new setup every time any kind of bass hits, the battery voltage meter on the dash goes completely crazy. But with the last subwoofers I had, it didn’t do much of anything. Anyways, I’m not getting much bass from the new setup and also they make a loud popping noise when I turn it up too high. The audio shop said my subwoofers were bottoming out. I was just wondering if poor electrical could cause little bass and bottoming out the subwoofers. My gain is set correct along with every other level adjustment on the amp. Also if they are in fact clipping and not bottoming out, could poor electrical cause clipping also? I know my electrical is bad because my interior lights and the lights on the amp all dim, and the gauge goes crazy when bass hits but wasn’t sure if it could cause my symptoms. Thank you.