I actually have had a mouse die in my car before...
I left my golf bag in the trunk for a few days. I usually store it in the garage. Well My car alarm had a motion sensor inside and it kept going off at weird times, all hours of the day and night to the point where I would take it in to get serviced and everything checked fine. Well I parked my car for about a week while on vacation in a parking lot...in direct sun. It was a black car with black tinted windows.
I got VERY hot inside

Well after vacation I got in the car and nearly threw up from the stench inside! I left the doors open for an hour while going to pick up some air freshner. I searched the entire car for anything that could be making the smell. I went thru 2 spray bottles of air freshner a week. I got so sick of the smell I started tearing the interior out to figure out what stunk so bad. only to find a mouse the exploded yes exploded and stuck to the metal wire mesh stuff on the bottom of the passenger seat!! It must have died and then bloated in the extreme heat and well its skin from its stomach was pushed over its head and rear end, it really did explode.
I had the interior professionally cleaned and de-oderized after removing what was left of the mouse.