So I was leaving my parent's house to go get some gas then head home. Turned out of alley, then saw my gauges glow brighter than normal and thought it was just the street lights 'cause it went back to normal. Then got gas, started heading home, got onto the highway and saw my Temp gauge shoot near the red part and gauge lights were super bright (including headlights). So I went back to parents' house, could not find a flashlight (they're moving so a lot of things were gone). So I use my stupid cell phone light. Checked the alternator belt as best I could, felt to see if it was too tight/loose and it seemed fine. Battery seemed/looked like normal. Coolant was still full. So I headed home and every once in a while when I start to speed up the same thing happens. My logger read up to 18.4v, but COOL was still at 213.1 like usual yet my TEMP gauge was getting near the red mark scarying me. This also happens when I blast the A/C while cruising on the highway home, but it never happens when I blast the A/C at a dead stop. Only seems to happen when I accelerate, then after about 10 nerver wrecking seconds it'll go back to the normal 14.2 or so volts and lights go normal again.
I'm not very good when it comes to electrical stuff, so ideas of what it could be or what I could check let me know asap. I think if my car goes dead again it'll be the last time I drive it/own it

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