A car (or automobile) is a wheeled motor vehicle used for transportation. Most definitions of cars say that they run primarily on roads, seat one to eight people, have four wheels, and mainly transport people rather than goods. Cars came into global use during the 20th century, and developed economies depend on them. The year 1886 is regarded as the birth year of the car when German inventor Karl Benz patented his Benz Patent-Motorwagen. Cars became widely available in the early 20th century. One of the first cars accessible to the masses was the 1908 Model T, an American car manufactured by the Ford Motor Company. Cars were rapidly adopted in the US, where they replaced animal drawn carriages and carts. In Europe and other parts of the world, demand for automobiles did not increase until after World War II.

Reasons Your Heating System Isn't Working: 
It might sound a little funny, but your vehicle’s heating system is a part of its cooling system. the cooling system circulates a coolant through the engine that absorbs heat. that heated coolant then runs through the radiator, where the heat dissipates. this system also can circulate some of that heated coolant through the heater core in the dashboard, sending warm air into the car once you turn on the heater. the amount of hot air and which direction it blows are controlled by the buttons and switches on your dash, which direct the heater valves and the car’s blower fan. 

A/C Is Not Blowing Cold Air Or Is Blowing Warm Air: 
While there are a variety of reasons your car's air conditioning might not be operating at top performance, the most common are a refrigerant leak, an electrical climate control issue, or a problem with the air conditioning compressor. each of these can cause the ac to blow lukewarm or hot instead of cold air. 

Car Leaking Oil? 
Oil is an essential fluid for the health of your engine, and it’s much better for your car, truck, or suv it all stays inside, where it belongs. unfortunately, it can work its way out and leak onto the engine or other parts, and then to the ground underneath. these leaks can simply be minor annoyances, or they can be serious threats to the life of your engine. it’s essential to know the difference so that you can avoid expensive repairs or getting stranded. 

Your Ignition Key Won't Turn: 
There three main reasons why an ignition key will not turn. these include, issues with related components, issues with the key itself or issues with the ignition lock cylinder. Safety first! before you start troubleshooting this problem, make sure that your vehicle has the parking brake applied. 

Car Engine Overheating: 
There are many reasons your vehicle could be overheating, but the most common include a coolant leak, a bad radiator fan, or a failed thermostat. these factors can contribute to an overheating in different ways. Coolant leak, bad radiator fan or failed thermostat. 

Rough Idle Causes: 
If your car's idle is rough, possibly rising and falling, or struggling to maintain a steady rate of rotation, you may have a problem that needs fixing. since a smooth idle depends on just the right mixture of fuel and air, there can be many possible places where that combination is getting unbalanced. 
Some causes: dirty fuel injectors, spark plugs, spark plug wires and ignition coils, air filter, pcv valve, egr valve, oxygen sensor, vacuum leaks.

Source: 
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