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An engine block heater is a small heating device installed in the engine that plugs into a wall socket. It warms the engine and oil and eases start-up. Engine block heaters are not expensive, but they must be installed properly by a mechanic. Your car's battery can deliver much more power when it's warm. You can do this using a battery wrap. A battery wrap or blanket is usually a fixed installation of insulation and heating element around the battery.  They require about an hour to sufficiently warm the battery. Parking indoors, in a garage, helps to shelter a car's engine from icy winds and freezing temperatures. Heat the garage, if possible, to keep the temperature warmer. In the extreme cold, oil thickens and doesn't flow quickly to vital engine parts that need lubrication. A lightweight, winter-grade oil flows easier in cold weather and increases fuel economy. Your owner's manual should tell you the ideal type of oil you should use. Gas line antifreeze, also known as dry gas, is a chemical (essentially Methyl Hydrate) that is added to your gas tank to inhibit your gas line freezing. If your gas line freezes, your car will not be able to start until it thaws.  Many gas stations already add an anti-freeze agent into their gas during colder weather months.  Check with your station of choice and see if this is their practice. Add dry gas to your petrol or gas fill-up before filling the tank (if possible) to ensure it mixes completely in the tank. A fuel conditioner is a multi-functional diesel fuel additive. A diesel engine will start better in the cold if you use fuel conditioner, which prevents the fuel from "gelling" and ensures reliable fuel performance in severe winter conditions. Condensation on the walls of a gas tank will form and will eventually sink to the bottom and cause freezing problems in your fuel lines. It's much more difficult to start a cold car with a mostly-empty tank, so do yourself a favor and gas up often in the winter before letting the car sit.

Summary:
Warm the engine with a block heater. Keeping your car's battery warm. Park indoors. Use thinner oil. Use gas line antifreeze with fuel stabilizer. For diesel engines, consider using fuel conditioner. Keep your fuel tank full.