When people talk about thermostats, they’re typically referring to the ones in their home appliances. You know, the one in any machine that involves heat exchange like a fridge, dryer, and so on. The truth is, there is one more type of thermostat that serves us daily: the car thermostat.

That’s right! Deep inside your car is a small thermostat that silently plays its part to ensure our engines never overheat. You may be surprised to learn about this component since rarely do people talk about it.

But you see, there’s a reason for that. Most people never discuss the car thermostat because there’s no need to. They’re straightforward mechanical devices that last for many years. Some may even last longer than the car itself!

Yet, just like any other car part, there is such a thing as a bad thermostat. These parts can fail somewhere along the line, causing you problems and forcing you to pay the thermostat replacement costs.

So, how do you know if your car ever needs a new thermostat? Let’s find out.

What Does a Car Thermostat Do?

Let’s start by getting on the same page about what a car thermostat actually does. Somewhere among your car’s many hoses sits a thermostat. It’s a mechanical device (i.e. it’s not electrically-powered, and it’s not connected to your battery or anything else). As a thermostat, it opens and shuts depending on the temperature that it’s exposed to.

When it opens, it allows coolant to flow into your engine and circulate. The coolant will then absorb some of your engine’s heat and prevent it from overheating.

Simply put, when your engine gets hot, the thermostat will allow more coolant to flow freely. When the engine is at the correct temperature, the thermostat will close and prevent excessive fluid from circulating.

Day in and day out, that’s all the car thermostat does. It’s simple, straightforward, and that’s why it typically lasts for so long.

What Happens When the Thermostat Goes Bad?

Your car thermostat may seem like a simple component. When you compare it to everything else under your hood, it’s definitely one of the simplest ones being used. But don’t underestimate it. As simple as it might be, it plays a critical role.

After all, I’m sure everyone can agree that there’s nothing worse than a car engine overheating!

So, what happens when the thermostat goes bad? Well, you may have guessed it already. A faulty thermostat might stay shut and prevent any coolant from circulating through the cooling system. That will lead to your engine overheating and forcing you to turn the vehicle off to stop the car from damaging itself.

But wait! The other possibility isn’t so good, either. Remember: a car engine can’t operate if it’s not hot enough. That’s why there’s an ideal temperature for an engine to run; not too hot, not too cold.

A faulty car thermostat could get stuck open and allow too much coolant to flow through. That will make it difficult for the engine to warm up enough to reach its optimal temperature.

How Do You Know When a Car Thermostat Goes Bad?

To put it in one sentence: you’ll know your car thermostat is going bad if your car overheats or doesn’t heat up for no apparent reason.

Sure, cars can overheat for several different reasons. But assuming you don’t notice any leaks on the floor under your vehicle and it still overheats, the problem could be with the thermostat that’s failing to let coolant circulate and cool down the engine.

Besides that, a car that doesn’t heat up to its optimal temperature could also suffer from a bad car thermostat. With all the combustion that goes on in the engine, it’s not normal for it not to heat up to its optimal temperatures.

Another hint may also be the Check Engine light. Yes, that light can refer to many different problems. But suppose you see it come on and notice the car overheating or not heating up enough at the same time; that combination could be a sign of a thermostat problem.

Can You Still Drive with a Bad Thermostat?

No, you can’t drive with a bad thermostat. That’s especially true if the thermostat is stuck in the closed position described earlier because that means the engine will overheat very quickly and cause damage to itself. And with zero coolants in circulation, that engine will overheat sooner than you think!

Driving an engine that’s been overly-cooled (i.e. when the thermostat is stuck open and circulates too much coolant) isn’t a good idea, either. Sure, your engine will turn, and your car will undoubtedly move, but you’d be subjecting your engine to excessive wear.

That’s because the engine’s fluids, lubricants, and components all work at their best only when the engine is at optimal temperatures. So, for instance, a lubricant that hasn’t had a chance to warm up sufficiently will not flow and do its job like it's supposed to.

With that in mind, if you’re going to drive while your engine is too cold, it’d better be straight to the workshop to replace the thermostat immediately.

How Much Does It Cost to Replace a Thermostat in a Car?

Alright, so you understand that there’s a problem and you want to get it fixed. But what is the average thermostat replacement cost in Australia?

A safe estimate to replace a bad thermostat is between $150 and $250. Just like any other car part, however, the exact figure will depend on your car make and model, the brand and quality of a thermostat that’s compatible with your car, and workmanship costs.

As mentioned earlier, a thermostat typically lasts a very long time. So, there’s no harm checking with reputable used car parts sellers to see if they have one that can still be of use to you. That might be an excellent way to save some money and solve your problem, all while giving that used thermostat a second lease at life.

(Blog from carpart.com.au)