The cooling system of modern cars like Audi A4 is maintaining the operating temperature of the engine for increasing its fuel mileage and performance. But when the antifreeze amount is lower down, then the engine is overheating and cause internal coolant leaks. Moreover, the internal coolant leaks in your Audi A4 are causing a hazardous situation for its engine. Go through the following slide to determine the causes and symptoms of coolant leaks in your Audi A4.