I've got an issue where my 4Runner is stalling when I'm slowing down, but only when it's wet. For instance, I can run it through a car wash, and everything works great, idles throughout the wash no problem. Then when I start going down the road and come up to a stoplight, it will bog down and stall. I can restart it immediately without any issue. Today, it was also bogging down while I was driving, but as soon as I let off to start slowing it stalled. Previous owner said that it would do it in the rain, but I hit some heavy rain after the car wash (car wash was only to test to see if my wiring changes helped), and it didn't have the issue . I didn't get a video of the dying after the car wash though.

I have replaced major wiring (block grounds, starter cable, chassis ground, added grounds, basically big 3 without adding alt pos). I have replaced spark plug wires (NGK) and coils. I have also replaced the vacuum lines, but I think that's less related.

I haven't decided if it's related or just the exhaust (exhaust was replaced before I bought it), but I am getting a weird sound in a certain RPM range under load. I didn't pay close enough attention to this until testing the dying today, but it sounds like it's grinding even though it's not. I wonder if it's misfiring in a very weird way...Any thoughts here either way would be great!
https://youtu.be/wXar0BTnfrM