I've only seen it happen to a flipped over, burnt car, didn't have any problems with the normal burnt cars. On another save I saw it happen to zombies too. I have seen a few of them stuck in the car (burnt, flipped car as well).
Hello, In build 41.37, you can walk through a flipped car and get stuck inside of it with no means to get out. (I eventually got out with noclip from a mod) I don't think the mods I have installed are responsible as none of them concerns vehicles. If needed I can give files from my save as i did a backup before installing the mod to get out of it. Thanks for looking into it and have a nice day. Keep up the good work guys, your game is awesome!