voltage jumping around??

[MR-355-5sfTe]

alright, I noticed when I hit the brakes, or use a turn signal... the voltage drops instantly, but the is immediately back to normal.... it makes my headlights dim ( kinda like I'm flashing my brights ) I just noticed this after I installed a new amp and sub.... everything is properly installed, wired correctly.... could there be a bad ground somewhere causing this? I replaced my terminals before the install, hooked everything back up and it all seemed to work fine. but this evening I notice the voltage jumping because I had my headlights on..... any ideas...? I'll probobly just go back over everything I've changed since I noticed the problem... I hate electrical problems

[91MR2quickNA]

It might just be the voltage regulator compensating for more electrical usage. Even w/o a system, my 91 NA with the 100amp alternator does this when I step on the brake pedal. Now if the headlights dim everytime the bass hits in your sub, then you'd most likely need a capacitator or something.

It doesn't hurt to add more engine to body grounds though. 6-8 gauge ground wires are pretty cheap.

[MR-355-5sfTe]

well, it drops even when the stereo is not turned on.... which makes me think it was something that I changed to install the amp.... of course my alternator had 200K miles on it... it might be ready to go as well.

[Pineapple]

Replace all ground wire with 4ga wire. Also run a 4ga ground inside the car to internal ground points.

[MR-355-5sfTe]

sorry to waste everyone's time... I knew it was something simple that I had either overlooked or just didn't tighten............. turns out it was just a loose + terminal... thanks for the suggestions and help... now I just need a good ass-kicking.