Car Overheating Then Going back To Normal

Have you ever noticed cars pulled over on the highways or on long journeys to “cool down” the engine and radiator? You ask the owner, and they say the car is over-heated, and we are cooling it down? This may not be a common sight today, with the more advanced engines designed to take care of themselves. 

Have you experienced your car overheating and then going back to normal independently, without you interfering? Any idea why this could be happening? If you are puzzled and looking for answers, read to know the various possibilities.

How To Know Your Car Is Overheating?

You are driving or just idling your engine at the signal, and you notice the temperature gauge shows a higher temperature than what it did a few minutes ago. Your car is suddenly overheating without any reason. Some of the other car overheating tell-tale signs are:

  1. The hood feels hot
  2. A weird ticking noise from your engine
  3. You notice the coolant has leaked or is leaking on the ground
  4. You can smell the heat (heated or melting plastic/rubber smell)
  5. You notice steam emanating from the hood
  6. A distinctive thumping noise
  7. The engine generates lesser power

Why Does A Car Overheat?

A car engine is designed to cool down as it runs. A coolant helps keep the engine temperature in check and ensures the engine does not overheat.

If there is a technical fault in one of these mechanisms, it can cause your car to overheat. 

Why Does the Car Get Overheated And How Does it Get Back to Normal

A car can overheat when it has been running for a long time or even when it is just idling but is it going back to normal? Here are some possible reasons for your car to behave this way:

1. Thermostat Is Spoilt

Most of the time, when a vehicle overheats, it is due to an issue with the thermostat. The thermostat helps regulate the engine’s temperature. It heats up and cools down to maintain the temperature of the engine. 

When this thermostat malfunctions, it does not effectively regulate the temperature, thus causing your car to over-heat and go back to normal without you having to do anything about it.

2. Fault In Radiator

Do you see the temperature gauge on your dashboard fluctuating? This could indicate your car radiator is heating up and cooling down abnormally. If you feel the car is over-heating, but the temperature gauge goes up and down, then it is a strong indication that something is wrong with the radiator fan.

When the radiator fan does not switch on when needed and works continuously to maintain the temperature, your car can overheat. If you lose your coolant faster than you should, this can happen.

3. Sensor Failure

The sensor picks up the data and sends it to the control unit when the car heats up. When this does not happen smoothly due to a fault in one of the sensors, the temperature is not well regulated, thus leading to over-heating.

When the sensor sends false or inaccurate readings to the control unit, it acts on that data, which can cause fluctuation in the temperature.

4. Shortage Of Coolant

Coolant moves around your engine, absorbing the heat and helping cool down the engine.

Now, if you are losing coolant faster than expected, you will be running low on coolant; or if you have forgotten to refill the coolant, it can be insufficient to cool down your car.

5. Water Pump Leak

If your car seems to be heating up when you are driving, it could indicate a leak in the water pump. If your water pump is old and has reached its limit, it can start leaking due to wear and tear.

When it starts leaking, your coolant will also leak, thus resulting in the car over-heating and returning to normal when you are driving.

6. Coolant Switch Failure

Is your temperature gauge rising uncontrollably despite you trying everything to control it? It could mean the coolant switch is malfunctioning.

When the coolant switch does not function properly, the coolant does not circulate to cool down your car engine. As a result, it keeps heating no matter what you try to do.

7. Low Engine Oil Level 

Your engine requires oil for smooth functioning. If there is insufficient oil in the engine, it can increase the friction thus leading to a temperature increase.

So the lubrication will not be consistent and sufficient and make your temperature gauge go up and down continuously.

What Can You Do?

Ok, so your car is overheating and going back to normal on its own. What can you do to prevent such a fluctuation in the temperature, which can damage your car in the long run? You can give these ideas a try:

Vehicle Diagnosis

If your car is over-heating and going back to normal on and off, you need first to get your car checked. Ask your trusted mechanic to perform a diagnostic on your car.

They may have to drive your car around to diagnose the problem. Since the car is over-heating while running or idling, it may not be possible to diagnose with the engine off. 

A well-experienced and trusted mechanic should be able to identify the problem before they randomly change things in your car. 

Replace Faulty Thermostat

If you identify the source of the problem to be your thermostat, replace it. A mechanic will check this first before anything else. Even if they cannot diagnose perfectly, they will try replacing the thermostat.

Only if this does not solve the issue will they touch other parts. (unless they can find the actual cause for the fluctuation)

Check For Coolant Leak

Coolant leak is a common problem. Check if there are wet patches under your car when parked. If you identify a leak, get a mechanic to fix it and identify what else could be the reason for the leak and fluctuation.

Replace Radiator

If none of the above work, it could be your radiator. If your mechanic can identify the source of the problem as your radiator, you will have to replace it. 

Conclusion

A car engine is designed to take care of itself, including temperature control. If there is an issue with the engine’s temperature, you need to address it immediately.

Letting your car run when it is constantly over-heating can cause severe damage to your engine.

Liam

Hi, I'm the initiator and writer of this blog. Cars were and will be my first love, and my favorite hobby, that's why I decided to start this blog and write about my discoveries and techniques to improve my cars or repair them.