5 Signs Your BMW Thermostat Needs To Be Replaced

The majority of you are likely familiar with thermostats and what they do. For those who don't know, it's a part of the engine cooling system—which essentially controls the coolant circulation between the engine and the radiator. This prevents the engine from overheating or over-cooling. Thus, it is obvious that if the thermostat malfunctions, the engine will overheat.

The good news is that it's not difficult to recognize the signs of a defective thermostat. Our discussion in this blog post will focus on the signs of a malfunctioning thermostat. Let's start by discussing how it works.

How Does An Auto Thermostat Work?

In a nutshell, a thermostat is a mechanical device that functions under the laws of simple physics to control coolant circulation between the engine and the radiator. Some of its major components are a wax element, main spring, main valve, bypass spring, bypass valve, flange and pin.

The wax element is its centerpiece. You can think of this element as a temperature-sensing component that can change its form between liquid and solid in response to the coolant temperature. If for some reason, the wax element or other parts of the thermostat wear out; your engine may overheat or become too cold.

Now that you know what a thermostat is and what it does, let's discuss what happens if it goes bad.

How To Know If Your BMW Thermostat Needs To Be Replaced?

Below are a few signs that may indicate it's time to examine your BMW thermostat;

Engine overheating / overcooling

This is, frankly speaking, the first thing you will notice in the event of a thermostat malfunction in your car. The thermostat works along with the water pump, radiator and other components of the cooling system to keep the engine temperature somewhere between 195 to 220 degrees Fahrenheit.

If the thermostat malfunctions, the cooling system will stop working—which can result in the engine overheating or underheating. Long story short, if your car engine is running hot, have someone check on its thermostat. And, if the thermostat is working fine, get the other components of the cooling system tested.

Coolant spilling out

A coolant leak is another typical sign of a thermostat malfunction in a car. The coolant, however insignificant this fluid may seem, plays a vital role in keeping the engine temperature within an acceptable range. And, to do so, it moves continuously between the engine and the radiator via the thermostat.

Any damage to the thermostat can result in a coolant leak in your car. And, guess what... If you ignore this leak and don't replace the faulty thermostat, your engine could overheat. And, driving a vehicle with an overheated engine can lead to some serious problems- which can cost you thousands of dollars.

Weak engine performance

If you're having trouble accelerating your BMW, it could be a sign that your thermostat has gone bad. The thermostat, as you would have read earlier, is a device that essentially works in close coordination with the water pump and other components to control coolant circulation between the engine and the radiator.

By doing so, it ensures that the engine temperature stays within a particular range (195 to 220 degrees F). If it malfunctions, the engine temperature will often rise beyond this limit. As a result of which you will see a drop in torque output by the engine.

Temperature gauge fluctuation

Another common finding in a vehicle with a faulty thermostat is fluctuating engine temperature gauge readings. So if you notice that your vehicle's temperature gauge has been behaving abnormally lately, take your car to a nearby car service center and ask someone to check its thermostat.

Flashing engine light

Sometimes a faulty thermostat can trigger the check engine light. How is this possible, you asked? Well, if for some reason the thermostat breaks down, the engine will overheat—which may prompt the onboard diagnostic system to turn on the check engine light.

Final Thoughts

So, these are some of the most common symptoms of a faulty thermostat. If you ever notice any of the above symptoms, check the status of the thermostat immediately. And, if the thermostat seems fine and you are not sure what's wrong with your vehicle, contact an ASE-certified mechanic in your locale.

If you are searching for a German automotive repair shop that possess higher levels of quality in the design work, manufacturing and performance, then we at Escondido German Auto are the perfect destination for your car.