OK, so I fixed my random dying issue, but I have a new issue.

At times, and especially when at stoplights when the A/C is on, my engine will literally "thunk" and the idle will stutter randomly, drop, and rebound instantly with each thunk. This also happens a lot more in warm weather than in cool, even if the A/C is off.

It's been very dry where I live, but this morning, I decided to go through a car wash for the first time in awhile, and as soon as the undercarriage wash kicked on, this happened again and it killed the car. I was eventually able to get it restarted.

This sounds electrical to me. Any thoughts? Loose or exposed wire maybe?

 

No clue, but I would definitely avoid using those car washes as they are full of grit and crap that will scratch your paint.