An Audi’s thermostat is a significant component of the engine cooling system. It sits between the engine and the radiator and is about 2 inches (5 cm) in diameter. The function of the cooling system is to keep the engine from overheating.

In most homes, you will find a thermostat. It will maintain the desired temperature range. When your house gets too hot, the air conditioning is activated, inversely, when it gets too cool, the heater turns on. That’s exactly how the thermostat works in your Audi for your engine.

Your Audi’s engine works well at a certain temperature that is warm enough to efficiently run but not so hot to cause engine malfunction. The thermostat reduces engine wear, emissions and deposits by letting the engine warm up quickly. The thermostat separates the engine from the radiator until it has reached a certain bottom temperature. Without a thermostat or faulty one, the engine would always lose heat and take longer to warm up.

The Importance of the Thermostat

When you first start your car, the engine is cold while the thermostat is closed. This allows the coolant surrounding the engine to warm up to the appropriate operating temperature. The thermostat opens as the coolant heats, allowing the coolant to flow through to the radiator to lose the heat.

The coolant flows through the engine where it absorbs the heat being generated by the engine, ending up at the top of the radiator. Air passing through the radiator cools down the coolant as it flows down the radiator.

The trick of the thermostat is in the small cylinder on the engine-side of the device. The cylinder is filled with a wax that melts at 180 degrees F. A shaft attached to the valve pushes into this wax. As the wax melts, it expands and pushes the rod out of the cylinder, opening the valve.

The electric fans attached to the back of the radiator automatically turn on when needed to allow more air to move through the radiator to increase the cooling. A water pump will then pull the coolant from the radiator and move it back into the engine.

Warning Signs of a Failing Thermostat

Your Audi’s thermostatic needs to be functional at all times for optimal performance of your car. We can divide symptoms of a bad thermostat in your Audi into two types: stuck closed and stuck open.

Stuck Closed

When the thermostat is stuck closed, it might cause the engine to overheat. Most commonly, it is because of low water level, a blocked radiator, or a malfunctioned cooling fan. It also may be caused by a failing water pump, clogged the radiator, or the engine itself.

If the thermostat is stuck in the closed position, the circulation of the coolant is obstructed and hence the coolant cannot get to the radiator to be cooled, which causes engine overheating.

Stuck Open

If your car is running unusually cool and not building up any heat in the engine, it’s likely that your thermostat is stuck open and is letting too much coolant. When the thermostat is stuck open, the engine temperature drops below normal when driving.  It will reduce the efficiency and fuel mileage of your car.

Performance Depends on a Functional Engine

We know Audi for its stylish superior manufacturing and cutting-edge technology. If you own an Audi, you know driving it is a privilege and comes with an air of pride and you want to keep it performing immaculately. If your thermostat fails, the engine will not work within its ultimate temperature range. This will affect the performance of your Audi.

If you experience overheating, low temperature, erratic temperature reading and coolant leaks visit us at Dell’s Service Center for the best services in Green Bay, Manitowoc, and Sturgeon Bay, WI.

Service You Can Trust for Your Audi

At Dell’s Service Center, we are proud to offer reliable services for all Audi, BMW, Jaguar, Land Rover, Mercedes, Mini Cooper, Porsche, Volvo, Saab, Volkswagen. We have built a strong reputation for delivering high-quality auto repair services to European motor car owners.


Our highly qualified and experienced mechanics at Dell’s Service Center are headed by an ASE Certified Master Technician. We specialize in quality service without a heavy price tag, because we believe in treating every customer with the integrity that they deserve. We pride ourselves on helping Green Bay drivers get back on the road quickly and safely without long wait times or ineffective service.

Dell’s Service Center is dedicated to helping drivers in Green Bay, WI and the surrounding areas. If your European vehicle needs maintenance or repairs, we are only a call or click away. We are open Mon-Fri: 7:30am to 5:30pm. Stop by our auto center at 840 Van Der Perren Way in Green Bay or make an appointment today by calling (920) 494-2860.

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