The very first cars built back in the late 1800s ran so rich they produced very little CO2. They had so much fuel going through the engine that the exhaust would burn your eyes and poison anyone standing next to the exhaust.
It was about the mid 1950s before cars started to produce higher levels of CO2. By the 1970s, with more efficient engines and pollution controls, the CO2 levels went up to as much as 14 percent of the exhaust, all the way from 5 percent or more back in the late 1890s before indoor Heating and Electricity and two-way plumbing in your Home.
Cars still do not have sewer plumbing.