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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 an Engine Lubrication System Works

Unlike the ever-present ads for drugs on television, there are many pleasant side effects of keeping your car's engine lubricated with oil. Find out what it takes to keep things moving.


 What is the difference between a normal lead-acid car battery and a deep cycle battery?

What is the difference between a normal lead-acid car battery and a "deep cycle" battery? I have a trolling motor on my boat and I don't see why I can't use my car's battery with it rather than spending another $80 on a deep cycle battery. See more »

 How does the thermostat in a car's cooling system work?

How does the thermostat in a car's cooling system work? I had to test my thermostat today and was amazed as I watched it! See more »

 What does the battery light on the dashboard mean?

The battery light on my car dashboard comes on whenever I am driving. How serious is this? The car seems to be working fine... See more »