Your Mercedes engine uses a thermostat to accurately record the temperatures inside the engine. This information is displayed to the driver through the temperature gauge, which can be found on the dashboard. While some engine temperature fluctuation is normal and can be affected by factors such as the temperature outside when driving, it should remain at a steady level.
Aside from when it first starts, which is where the engine can appear to be running hot or cold before leveling out, any temperature fluctuations need to be carefully monitored and inspected by a professional technician if they persist. With this in mind, let’s take a closer look at how you can deal with thermostat failure in your Mercedes.
Reasons for Thermostat Failure
There are 3 main reasons why your thermostat may fail, and the first is actually a misdiagnosis. Remember that the thermostat isn’t responsible for telling the driver the temperatures inside the engine. Its only role is to record the data and relay it to the temperature gauge.
Therefore, a fault temperature gauge can often lead to the misdiagnosis of the thermostat. This is why it is important to seek professional repairs when faced with an automotive issue as you can save yourself the time, money, and stress associated with misdiagnosis.
The second reason for thermostat failure is coolant leaks. Coolant leaks can happen for many reasons, but your thermostat may also be a contributing factor in this. When your thermostat becomes old, it can prevent coolant from properly circulating the engine. This ultimately leads to your engine overheating which can cause some serious damage, but you may get a warning sign in the form of a coolant leak emanating from around the thermostat. Your technician will use a differential diagnosis to see if this is the case.
The third reason for thermostat failure is simply the failure of the part itself. All car parts can become worn out over the years, and if your Mercedes is an older model you may reach the point in your car’s lifespan where even long-lasting parts will need replacement. You’ll know if the thermostat has failed because it won’t be able to properly record and regulate temperatures inside the engine leading to performance issues and overheating.
Thermostatic Valve Failure
The thermostat itself is attached to a part known as a thermostatic valve. This part uses the temperature readings from the thermostat to open and close a valve, which allows or blocks the flow of coolant to the engine system. When the engine is too hot, for example, the valve will open allowing coolant to reduce temperatures. When the engine is running cold the valve will close, blocking coolant flow and allowing the engine to warm up.
Oftentimes, thermostat failure isn’t because of the thermostat itself but because of the valve becoming stuck in the open or closed position. When this happens you’ll notice the following:
Thermostatic Valve Stuck Open
When the valve is stuck in the open position, coolant is allowed to continuously flow around the engine. This causes the engine to run cold. When an engine is running cold, it experiences a drop in overall efficiency. This means that fuel consumption and emissions levels will increase. Cooler running temperatures also contribute to the acceleration of part wear.
Thermostatic Valve Stuck Closed
When the valve becomes wedged shut, the coolant isn’t able to do its job and reduce engine temperature. This will result in engine overheating. The consequences of a closed valve are far worse than an open valve, as high heat can quite literally cause an engine to destroy itself. Parts will warp and bend due to the phenomenal heat that your engine can produce. Either eventuality, however, does have negative ramifications for your vehicle, so it needs to be addressed swiftly.
Bavarian Auto Will Fix Your Thermostat Problems
It’s not advisable to try to deal with thermostat failure yourself. Reaching the thermostat or its valve may be tricky, requiring special tools to disassemble the parts. If you don’t know what you’re doing, then you may end up causing further damage. DIY repairs also do not give you the guarantee of a long-lasting or even suitable fix.
Instead, bring your Mercedes to Bavarian Auto of Ootelwah, Hixson, and Chattanooga, TN. As our name might suggest, we’re the experts in German manufactured vehicles. If you want to guarantee that your motoring problems are fixed the first time around and won’t fail you miles down the road, then make sure to bring your Mercedes to Bavarian Auto.