Why does your car run cooler with the AC on?

It's a common misconception that your car runs *cooler* with the AC on. In reality, running the AC puts more load on the engine, which *increases* engine temperature slightly. However, the car's cooling system is usually more than capable of handling this extra load.

The reason it *feels* cooler inside the car with the AC on is because the AC is actively removing heat from the cabin, making the *interior* of the car cooler. This has nothing to do with the engine temperature itself. The engine's temperature is managed by the radiator and cooling system, regardless of AC usage.