Idea for a TV show
(I had to look up 'econobox' - apparently its an American term for a normal European / Japanese car)
Two brilliant inventors: one a megalomaniac, one a humble tinkerer. The Megalomaniac has invented a massive robot, the size of a moon, with which they are attempting to conquer parallel dimensions. The Tinkerer has packed a pocket universe into a fuel efficient, practical hatchback, filling it full of contraptions and tools. They travel the multiverse in their little yellow car, using their pocket universe as a lifeboat, fixing the disasters that the Megalomaniac has caused and trying to thwart their terrible plans.