High temperatures can be brutal on your car's engine, and the entire country has been suffering under record highs all summer long. Add a traffic jam to this heat and you've got a recipe for an overheated engine. Taking good care of your car's cooling system is an important step in preventing overheating. An annual radiator flush will keep good, clean coolant flowing through your radiator and hoses. It's also a good time to find out whether your car's coolant level will fluctuate over time, either through tiny leaks or losing coolant through the combustion chambers. The more you know about your engine, the better.