A question recently dawned upon me: do cars explode when they are compressed at junkyards? It seems like the answer would be 'no', obviously, or else this would most likely not be common practice. But after seeing so many explosions in movies (and yes, I realize that they are just movies, but I still assume there must be some truth there), I am under the impression that crushing a car into a cube would pose this risk given the leaking fuel and possible sparks from metal grinding against metal.
Anyone have any insight on this?