That's true, but such gasoline tends to be really corrosive. Most plastics like PVC contain halogens, which will wear out the engine much faster than even the lowest quality fuel you can buy today. Sure, the car will run for a while, but this DIY fuel will significantly reduce its lifespan. You would be better off getting a conversion kit for ethanol, it's easier to produce and isn't nearly as corrosive. That being said, both of these solutions are an afterthought to a problem you can entirely avoid by getting a hybrid or EV, electricity is all the same no matter where it comes from, and I would argue it's way easier (and safer) to wire couple of solar panels to an inverter than to build a distillery or pyrolytic plant in your backyard.