Combustion is incomplete and you have other trace elements (and not trace - like fuel additives) in the fuel / atmosphere.
There's also a system on your car that pulls gas out of the crankcase and through the engine. It's full of oil vapor and singed fuel that only sorta burns on its way through the combustion chamber / cat.
RCrl t1_ja56lgb wrote
Reply to If the fuel that goes in car engines is extracted from hydrocarbons, which consist of only Hydrogen and Carbon, and those hydrocarbons react with Oxygen in the air (combustion reaction), to produce CO2 and H2O, why do we get a bad smell from car exhaust fumes if both gases are odorless? by Protoflare
Combustion is incomplete and you have other trace elements (and not trace - like fuel additives) in the fuel / atmosphere.
There's also a system on your car that pulls gas out of the crankcase and through the engine. It's full of oil vapor and singed fuel that only sorta burns on its way through the combustion chamber / cat.