That's why I like my old Toyota Landcruiser. There's no computer chip, and its designed for backyard servicing. I could drive that truck for a long time and probably still create fewer emissions than are created in the building of a new car. I'm dead if I have a big accident though.
There are businesses in Australia which will take cars with chips in them, and tune them to get the maximum power possible within the manufacturer's safety limits, also claiming better fuel economy.... One would think increasing the power would increase fuel consumption, and emissions, as we see here. What am I missing?