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Auto | Under the Hood | Other Systems

Learn about the various electrical and other systems that lurk under your hood, including cooling systems, ignitions, wires, fuses and connectors.

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How does a positive crankcase ventilation (PCV) system work?

Just seeing the phrase "positive crankcase ventilation" probably makes your head hurt, because it sounds, well, complicated. But it really isn't all that complex.


Do you need a secondary air injection system?

 Do you need a secondary air injection system?

Do you need a secondary air injection system? Read about the possible advantages of a secondary air injection system for your car. See more »

Do HHO systems actually work?

 Do HHO systems actually work?

Do HHO systems actually work? Read about HHO fuel systems and whether or not they're a legitimate alternative fuel or just science fiction. See more »

How Automotive Exhaust Systems Work

 How Automotive Exhaust Systems Work

What does an automotive exhaust system do? Read about the purpose of your car's exhaust system at HowStuffWorks. See more »

How Automotive Air Conditioning Works

 How Automotive Air Conditioning Works

Do you know how automotive air conditioning works? Read about the AC in your car at HowStuffWorks. See more »

How Evaporative Emission Control Systems Work

 How Evaporative Emission Control Systems Work

What is evaporative emission control and why does your car need it? Read about evaporative emission control systems at HowStuffWorks. See more »

Can a car seat recognize its owner's rear end?

 Can a car seat recognize its owner's rear end?

The inevitably sub-par posture and numb cheeks of a wary, worn-out driver can leave an imprint -- on the body, soul and car seat. Even the most well-worn saggy cloth or leather seat can hold the shape from its occupant for a few minutes, and it's nev ... See more »

How will the car of the future use biometrics?

 How will the car of the future use biometrics?

Biometrics sounds like the stuff of science fiction, but measuring biological markers to identify people is already happening. Scanning the swirls of our fingerprints or the individual markings of our eyes has been used for years by security professi ... See more »

 What do distributor caps and rotors do in ignition systems?

Do you know how distributor caps and rotors function in ignition systems? Find out how ignition systems work in this article from HowStuffWorks. See more »

 What are some symptoms of ignition coil failure?

Ignition coils are responsible for passing electricity on to your spark plugs. Learn about the symptoms of ignition coil failure in this article. See more »

 How does a radiator cap work?

The radiator of your car is composed of tubes that carry the coolant fluid, a protective cap that’s actually a pressure valve, and a tank on each side to catch the coolant overflow. Learn more about how a radiator cap works from this article. See more »