Your car's thermostat is a part that you may not think about often, but that is really important for the overall function of your vehicle. The thermostat is not a measuring stick like the thermostat that you may have hanging up outside your house.
It is a device inside your engine that sits closed until your engine reaches a certain temperature, and when your engine reaches that temperature, it opens up. It allows coolant to flow into the engine. It is a tool that regulates and controls your engine's temperature by regulating coolant flow through the system.
The thermostat fails when it doesn't open or close at the right time. If it is stuck open, the engine will not reach the right level of heat. If it is stuck closed, the engine will overheat. Here are some signs that you will notice when your thermostat is failing.
#1: Overheating
When your thermostat is not working correctly, your engine is going to overheat and quickly. When you look at the temperature gauge on the dashboard of your vehicle, you will notice that it hits the red within minutes of you starting your engine. Your vehicle's engine shouldn't overheat that quickly when the thermostat is working properly. This can cause serious damage to your engine, as it is not getting the coolant it needs to keep things chill. This will happen when the thermostat is stuck closed and the coolant isn't able to flow.
#2: Low Engine Temperature Reading
A low engine temperature reading on the flipside, which occurs when your engine's thermostat is stuck open. When it is stuck open, the engine isn't able to reach optimum temperatures before the coolant starts to flow through the engine. This occurs because coolant is constantly running through your engine.
The temperature needle will be located at the lowest possible setting when this happens. This can degrade the efficiency of your engine and create increased emissions.
#3: Erratic Temperature Changes
When the thermostat is not working correctly, you may notice the temperature gauge giving off erratic readings. One minute it will be really low, and then it will be extremely high in a few minutes. This happens when the thermostat isn't stuck but it isn't working properly.
Generally, your temperature gauge should gradually warm-up, and then stay at the same spot for most of the time you are driving. It shouldn't be bouncing around.
#4: Leaking Coolant
Finally, you may notice coolant leaking out around the thermostat housing on your vehicle. This happens when the coolant isn't able to flow and the thermostat is stuck. Over time, coolant may leak not just around the thermostat housing but also from other coolant hoses. Eventually, you may find coolant under your vehicle.
If you experience any of the signs of a failing thermostat above, get your vehicle to a local car repair shop right away. A failing thermostat is something that you should take seriously, as it can result in severe damage to your engine.