It was an intake manifold, so it's continuously under suction. At the temperatures in an engine bay the plastic probably gradually creeped to a point where the restriction increased the suction and suddenly it collapses completely.
Oh the suction, I wasn’t considering that. I was thinking of general compression or tension between the connections on the ends.
Oh the suction, I wasn’t considering that. I was thinking of general compression or tension between the connections on the ends.