A cold air intake is a device used to bring lower temperature air into a car's internal-combustion engine, to increase engine power and efficiency. It also enhances efficiency through higher flow, and can increase the life of the engine by allowing it to run cooler.

Standard air intake systems tend to be very restrictive, in order to eliminate engine noise. Aftermarket cold air intake systems come in many different colors and sizes, and are easy to install when compared with other performance-increasing modifications. Usually screw drivers a All cold air intakes operate on the principle of increasing the amount of oxygen available for combustion with fuel. Because cooler air has a higher density (greater mass per unit volume), cold air intakes generally work by introducing cooler air from outside the hot engine bay. However, the term "cold air intake" is often used to describe other methods of increasing oxygen to an engine, which may even increase the temperature of the air coming into an engine.