Why is your car overheating then going back to normal? Even when it can run, the sudden heat indicates that there must be some problems within the system.
Your car overheats for multiple reasons. Unfortunately, an overheating engine can lead to damage to the internal parts of your vehicle.
So let’s work together to find out the causes. Then, we can come up with the right solution for each cause.
Why Is My Car Overheating Then Going Back To Normal?
Your car overheats then goes back to normal mostly because of the coolant, radiator, or thermostat issues. Some relevant cooling system components, such as the cooling fan or the belt bummer, can also be the cause.
There is a small gauge with an H (hot) at the top and a C (cold) at the bottom on the dashboard of your steering wheel. This gauge displays your car engine temperature.
Your operating temperature should be right in the middle of this gauge. When it moves up to the H, your car is overheating. Then, it cools down and returns to the middle level.
Sometimes, the faulty parts in your car cause it to overheat and fail to start. Becoming normal after the sudden heat seems OK, but do not overlook this symptom. Here are some things you may encounter.
Low Coolant Level
The low coolant level is one of the most common causes if your car overheats then cools down quickly.
The coolant regulates the temperature of the engine as it absorbs and dissipates heat. If the coolant level in the reservoir is too low, the engine will overheat.
The low coolant level also causes different issues in your engine, such as engine damage. So do not ignore it if you verify that the coolant level is the root of the problem.
How to solve it?
Your car will either have an overflow bottle or a coolant tank, which you can check to read the coolant level.
To do this, unscrew your coolant cap under your car bonnet. If the cap is bone dry underneath, then you need to add more coolant to your car.
However, you must only do this when your engine is cool. The liquid will squirt out all over you if it’s still hot!
Faulty Radiator
If you experience engine overheating but coolant full, check for other possible causes. The radiator should be the first thing to suspect.
The radiator circulates coolant through the engine to absorb heat. It’s a series of tubes and fins that aim to transfer heat away.
Almost everything related to the coolant may make your car overheat when malfunctioning. In this case, the clogged or damaged radiator leads to the same issue. The broken radiator cap can be among the causes.
How to solve it?
When the engine is cold, unscrew the radiator cap and look inside. If it’s dry, then you need to pressure test the system to check for leaks in your radiator. You can do this by using a pressure leak testing kit.
Once you’ve hooked up the kit to the radiator, pump up the pressure for at least one minute. If the issue is your car’s radiator, you will see fluid leaking out of your radiator. It means that your radiator has some holes.
However, sometimes the leak could be smaller and harder to find. So, if you cannot see any fluid leaking out after the pressure test, keep an eye on the pressure gauge and see if it begins to drop. If yes, there must be a leak, and you have to find where the leak is coming from.
If there are no leaks after completing these checks, the issue may be with your radiator cap. These caps are supposed to hold pressure in. But if they’re worn and rusty, then you might just need to purchase a new one.
Faulty Cooling Fans
Your car overheating then going back to normal while driving may result from the faulty cooling fan. As the name implies, this component should cool things down. It pulls air through the radiator to dissipate heat and regulate the engine’s temperature. When it stops working, you will easily notice the heat in the engine.
How to solve it?
Start your car and turn the air conditioner up to the full blast. Then open up the bonnet of your vehicle and check to see if both your left and right cooling fans are working. If not, there will not be enough air extracted straight through the radiator.
Make sure to check your fan motors, too, as they can often burn out. You can get a small jumper wire and stick one clip on the car battery’s positive terminal. Then, insert the other clip on the red cable that feeds the fan motor.
If the fan doesn’t start spinning, then you’ll know the motor has burned out. You need to replace the fan motor soon.
Broken Thermostat
Your thermostat closes so the engine can warm up. When the engine gets hot, the thermostat should expand and open up. But sometimes, it may get stuck, which means your engine can’t cool down.
The broken thermostat may also cause severe damage, such as coolant blowing out of the reservoir.
How to solve it?
You can typically find your thermostat by following the bottom radiator hose. Once you’ve removed and replaced it, your car should stop overheating.
Clogged Catalytic Converter
No air can come out when the catalytic converter gets clogged because of the carbon buildup. As a result, the engine will overheat and lose power.
How to solve it?
Check the catalytic converter to ensure nothing is blocking the pipe. Unclogging this component is complicated and potentially dangerous. Hence, leaving this task to a qualified mechanic would be best.
Besides, to prevent blockage, you must regularly maintain the catalytic converter. Cleaning it is a good idea.
Malfunctioning Belt Bummer
The belt’s job is to rotate the pump, which pushes cooling through your system. However, the engine belt could come out of alignment. Then, the pump cannot turn and distribute the coolant. This issue results in the car overheating then going back to normal.
How to solve it?
To prevent this issue from happening, lubricate your belts and keep them tight. Believe us; this task should be done by a professional. So taking your car to the nearest garage is the best solution here.
Bad Head Gasket
The head gasket seals the gap between the cylinder and the engine block. The coolant and oil can’t mix because of the seal. Then, your engine compression can work properly.
The coolant will leak into the combustion chamber if the head gasket fails. Your engine will overheat as a result.
How to solve it?
The bad head gasket can tear your engine apart. Hence, you need to determine if it’s the case by carrying out a combustion leak test using a combustion leak tester kit.
You will pour blue liquid into a tube. Then, when the engine runs and the blue liquid turns yellow, you can tell that the head gasket has failed. Contact a mechanic soon to have this problem fixed.
Conclusion
Why is your car overheating then going back to normal? You can check the cooling system’s coolant level, radiator, and other components to detect the exact cause. Next, follow the tips we have shared to fix it.
It’s not easy to repair mechanical issues on your own. Hence, you should ask for professional help. This service can be expensive, depending on the broken part. However, to stay safe, you don’t have other choices.
Thank you for stopping by! And don’t forget to contact us for any car problems. We are always ready to help.
Hi! My name is Mark Stevens – the founder of Auto News Portal.
I wrote articles in the automotive industry for more than 10 years, published in USA, Europe and the Asia. I love sharing my knowledge and insights with fellow enthusiasts. Join me on this journey as we explore the exciting world of cars together!
