Why You Should Never Drive an Overheated Car 

Even if your car still has coolant, overheating can cause serious damage. Any leftover antifreeze can boil, causing damage to your radiator. Many parts of your engine — like hoses, seals, or cylinder heads — aren’t designed to withstand extreme heat. When hoses and seals start to blow, this can lead to serious leaks. As the heat warps your car’s cylinder heads, it can even lead to a blown head gasket. That can lead to coolant mixing with engine oil, an extremely costly repair that can total your car. And of course, there are all sorts of electrical wiring and sensors under the hood that can be damaged from the buildup of heat as well. 

If your dashboard warning lights tell you the car has started overheating, the most important thing to do is stop driving right away. Pull over somewhere safe and turn off the engine. Do not open the hood or attempt to put coolant in the radiator. The parts under the hood will be dangerously hot and can cause serious injuries; plus, the contents of your radiator may be highly pressurized and could blow if you break the seal. Once you’re safe and the car is turned off, call a professional mechanic and have the car towed. You should not attempt to drive again even after it has cooled off.