If I tell you that you can run your car on trash, your thoughts will skip immediately to the shiny Mr. Fusion used on all time-traveling DeLoreans.
(Mr. Fusion gets fuel in Back to the Future)
It turns out that there is a present-day (and non-fictional) way to run your car on trash. And that's by using gasifier to "convert nearly any solid dry organic matter into a clean burning, carbon neutral, gaseous fuel."
Did you know that over one million vehicles in Europe ran onboard gasifiers during WWII to make fuel from wood and charcoal, as gasoline and diesel were rationed or otherwise unavailable? Long before there was biodiesel and ethanol, we actually succeeded in a large-scale, alternative fuels redeployment-- and one which curiously used only cellulosic biomass, not the oil and sugar based biofuel sources which famously compete with food.
Watch Mr. Gasification - the trash-powered Honda - in action in this video.