The same reason a home fireplace needs a chimney. Cars burn fuel and air. The byproduct of this is exhaust gas. The exhaust gas needs to be expelled somewhere so it is piped out under the vehicle to the back where nobody will be breathing it.
Improve appearance
Some (front wheel drive) cars have a flexible piece of pipe that connects the exhaust manifold to rest of the exhaust system. The length of pipe is designed to allow the engine to rock back and forth on its mounts. Without the flex joint, the movement of the engine would damage the rest of the exhaust system.
Usually a product of valve overlap and exhaust. It's basically unburnt fuel coming through and igniting on the hot exhuast tip when it hits the air at the end of the exhaust pipe. In aspirated cars it's large valve overlap which helps scavenging and performance in the top end. Turbo cars, due to the large amounts of fuel at full noise. Normally happens after high RMP then throttle snapped shut.
Just make sure that the male cars do not ever get in touch with a female on the weekends. It could be catastrophic.
it is a emission device exhaust gas recirculation , it take exhaust gasses and by control of the cars pcm or computer and a egr valve it introduces a calibrated amount of exhaust back into the engines air fuel mixture.exhaust being mostly a inert gas will lower combustion chamber temperatures for a more efficient burn that will lower nitrous oxide emissions. its also re-burns left over hydro carbons that do not get burned in the combustion process
Cars do indeed produce exhaust, but they are not the only source of exhaust which can come form other forms of transport, house boilers and factories.
exhaust fumes of a car
Cars do not have anything in their exhaust to reduce carbon monoxide. A Catalytic Convertor in the Exhaust System is used to remove Carbon Monoxide from the exhaust gasses.
exhaust is spewed from cars and trucks.
Exhaust
do cars exhaust? yes
yes
Improve appearance
to decrease exhaust noise
because your gas tank is in the center
Many cars may have a version that includes a diesel exhaust system. Typically, these are trucks or large cars that need the extra power to continue driving.
Mainly exhaust from cars.