Literally happened like 15 minutes ago. My mom recently bought a BMW which I've been driving because she hardly uses it. At night she always wants it to be parked inside the garage.
I almost forgot to pull it in from the street tonight so I ran out there after everyone was asleep and pulled it in. As I pulled in I got a text on my phone and started reading it.
I sat there for a good few minutes until suddenly I didn't know what I was looking at and my hands felt weird and my vision started blurring in a really bizarre way.
Suddenly I realized that's because I was literally fucking dying because the engine was running in a closed garage and I was just breathing in carbon monoxide.
I managed to drag/roll myself from the car and get outside where I sat on the ground and for some reason cried a little bit.
Now I'm sitting on my bed eating a banana thinking about what an idiot I am.
TL;DR Gave myself carbon monoxide poisoning effectively killing off the single brain cell I had.
Edit: a few* words*.
UPDATE: I made it through the night without dying. Yes, the banana was great. A little underripe though.
I looked up what to do and mostly did just find "fresh air" as a fix for any exposure and thankfully I remembered how to breathe.
Also, for those of you asking it's not a brand new BMW, it's an older model but she just recently bought it so the engine doesn't automatically switch off.
Our garage is quite small as well so yes, it can happen in a few minutes!
UPDATE 2: Stop calling me "he." I'm having flashbacks to my childhood when my mom made me have short hair.