Car Thermostat Functions, Failure Symptoms, and Replacement Cost


In this article, we are going to explain
One important part of the engine systems and related to the cooling systems.
This part called the thermostat valve,
So, you will know the basic functions, failure symptoms and;
Also, the average replacement cost. And here we go:

Basic Functions

The main function of a car thermostat is to control the amount of coolant that goes into the engine. The thermostat will typically open whenever the engine starts to warm up. For example,
When you’re driving your vehicle for a while, the engine will get hotter. This causes the thermostat to open and let the coolant flow right through the engine. That way, it will cool the engine off and prevent it from overheating. On the flip side, if you leave your car engine running while you’re parked somewhere,
The thermostat will remain shut because the engine will already be cool from staying idle.

Also, read – How an engine cooling system works

A functional thermostat will know when the right time to open because
It has a sensor that detects the current operating temperature of the engine.
As you operate your vehicle,
The thermostat is normally open for most of the time
Because the engine needs to consistently be cooled off from the coolant. This sustains normal temperatures in the engine which helps it maintains the quality of its performance.

Go Pro For More HighlightsOf course, there are outside influences that may affect the temperature of the engine as well. The temperature of the environment around you is a perfect example of this. Cold and hot temperatures outside play a key role as to whether the thermostat is closed or open. But as long as you have a functional thermostat,
Then it will know when to perform either task.

Top 5 Failure Symptoms

When your car thermostat fails,
It will impair the operation and functionality of your engine. Fortunately, there will be some easily recognizable symptoms that you will notice when this happens.
You should take it upon yourself to replace your thermostat promptly
If it turns out that it’s worn out or faulty. If you don’t do this promptly,
Then your engine could suffer irreversible damage the longer it is overheated.


Below are the top 5 symptoms that will indicate a failing thermostat in your vehicle.

1. Temperature Change

The first noticeable symptom is when the temperature inside of your vehicle changes suddenly. It may start by dropping to a very low temperature and then suddenly;
Spike up to a very high temperature. Any change in temperature that doesn’t reflect
Your current air settings will mean that something is wrong with the thermostat.

2. Coolant Leaking

A faulty thermostat will likely cause it to remain in its closed position.
This means when the engine turns hot and the coolant flows toward it,
The closed thermostat will block the coolant from going into the engine.

This will cause the coolant to overflow from the thermostat housing. If it stays like this and you don’t do anything to fix it,
Your coolant hoses will be the next things that leak. The quickest way to see if you’re leaking coolant is to just check under your vehicle. If you see greenish liquid leaking
Out of your vehicle and staining the surface underneath,
Then you have a coolant leakage situation.

See More : Draining and refilling a fully sealed cooling system

3. Engine Overheating

Most drivers are used to their temperature gauge showing a normal temperature. However, if you have a faulty thermostat,
You will notice that the needle in the temperature gauge moving toward the red area very quickly. This indicates that the engine is unusually getting hotter and
It needs to be cooled off soon. This symptom should occur within 10 or 15 minutes of starting your engine.

4. Rumbling Noises

If temperature changes were not bad enough,
You will begin hearing strange rumbling noises as well. These noises will be coming from your radiator, engine, or both. The noise could also resemble a knocking sound,
Boiling sound, or gurgling sound as well.
If you’re hearing strange noises that you shouldn’t be hearing and
You experience one of the other symptoms listed here,
Then you most certainly have a thermostat problem.

5. Heater Malfunctions

If you live in a northern environment where it is colder outside,
You may the opposite temperature problem in your vehicle.
Sometimes when the thermostat is faulty,
It could be stuck in the open position rather than the closed position. This means it will keep letting coolant flow into the engine,
Even when the engine doesn’t need it. If you’re trying to produce heat in the wintertime and your thermostat is open,
Then you won’t get the heat that you want to warm yourself off.

Replacement Cost

The uplifting news for those with a defective indoor regulator is that
It doesn’t cost a ton of cash to have it supplanted. The specific cost will rely upon the make and model of your vehicle. Be that as it may, for the normal vehicle proprietor,
You can hope to pay somewhere in the range of $150 and
$200 for an expert specialist to supplant the indoor regulator in your vehicle for you.

Also, read – Car Radiator Heating Up? 5 Radiator Fan Problems That You Need To Know

To separate this normal cost, it is isolated into parts cost and work cost. The expense of the genuine indoor regulator unit itself is somewhere in the range of $30 and $60. The expense of the work will be somewhere in the range of $110 and $150. Recollect that most mechanics will charge around $90 to $100 every hour for their administrations. The indoor regulator substitution work isn’t that convenient,
However, it could take a repairman around 1 to 2 hours to finish it.
Along these lines, you wind up paying more cash for the work;
Then you accomplish for the real indoor regulator part.

Also, read – Checking and topping up car antifreeze coolant

A lot of vehicle proprietors attempt to set aside cash by supplanting the indoor regulator themselves. Except if you are an expert or experienced specialist,
At that point you better let an expert do the swap work for you.
All things considered, there might be
Another issue with your vehicle also. You’ll need an expert so they would first be able to
Analyze the issue before supplanting the indoor regulator.

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