It can be very frustrating to notice a continuous increase in your vehicle’s temperature gauge while driving. Trust me. I know that feeling. It ain’t funny. This sign indicates that the engine of your vehicle is rising in temperature, which is a problem.
Drivers who do not know what to do get even more frustrated. But do not too worry, cause today I will educate you on the causes of your car running hot but not overheating and also how to still get to that meeting or event on time even when you find yourself in this situation.
Just so you know, it is much better to notice this problem early so you can prevent it from aggravating to something else or rather, something worse that will demand a high cost of repairs.
As a mechanic, I found out that most drivers don’t even pay attention to the temperature gauge of their vehicle until they see the engine check light on.
The temperature gauge is a device used for measuring and controlling your vehicle’s engine temperature. Ideally, this gauge indicates the engine’s average temperature, which signifies that it is neither too hot nor cold.
When the temperature gauge is rapidly increasing, it reflects a drastic increase in the temperature of your vehicle’s engine, leading to the engine knocking.
The fact that the temperature gauge is increasing in temperature level does not certainly mean that the engine is overheating. It might also be a result of a faulty temperature gauge.
Symptoms A Car Running Hot But Not Overheating
These issues all have different symptoms that may indicate what the problem is:
#1. If The Temperature Gauge Reading Fluctuates.
This is for those moments that the temperate seems to rise dramatically and then go back to normal.
Perhaps you are stopped or accelerating on the highway, and all of a sudden, your temperature gauge is reading high, but the moment you go to check out the issue, the temperature has returned to normal. What is the problem here?
The problem is rarely the temperature gauge itself. While not impossible, the gauge is generally known to outlive the life of the car. Instead, the temperature gauge gives some indication of what the problem may be.
The most common reason for a temperature fluctuating in this way is a broken thermostat. Thankfully a thermostat is relatively cheap and easy to replace.
A dying radiator fan may also be the cause. If it is the fan, you may notice the fan making a strange noise, and you will be able to see it spinning weirdly.
The cylinder head gasket may also be a culprit. When the engine gets hot, this is often the first thing to break. A damaged gasket will cause a coolant leak into the engine oil. Lastly, if you don’t have enough coolant, you may have this problem.
#2. If The Temperature Gauge Reading Is High.
If your temperature gauge is consistently running high, there may be four reasons for this. One, it may simply mean that your engine is overheating. Two, you may be leaking coolant.
Three, like the fluctuating temperature, you may have a broken thermostat. And finally, if your car is running hot, it may mean that you need your water pump or water pump basket replaced.
#3. If The Temperature Gauge Reading is Low.
If you notice that your engine is steaming, but your temperature gauge is still reading low, then there may be some reasons for it.
One, if you notice that the temperature gauge is still reading as cold even after the vehicle has had time to warm up, then it may be the temperature gauge itself that needs to be replaced.
Generally, the temperature gauge will only read cold when the engine isn’t running. Second, it could be that the thermostat is stuck open.
In the case that the vehicle is overcooled, the thermostat can get stuck open, meaning that it will only read cold afterward. In this case, the thermostat will need to be replaced.
What are the causes of the car running hot but not overheating?
It can be a puzzling and frustrating situation to find yourself in. There are several possible reasons why this might be happening, so let’s explore eight of them.
#1. A Faulty/Clogged Cooling Radiator.
A common culprit behind this issue can be a faulty or clogged cooling radiator. A radiator plays a crucial role in keeping the engine cool by dissipating heat from the coolant circulating through its tubes.
If the radiator becomes clogged with debris, dirt, or mineral deposits over time, it can hinder proper heat transfer and result in an engine running hotter than usual.
#2. Insufficient Engine Coolant.
Engine coolant is crucial in keeping your vehicle’s temperature within optimal ranges, preventing it from overheating. If there’s not enough coolant circulating through the engine, it may cause the car to run hotter than usual.
There are several reasons why your engine might be low on coolant. One possibility is that there could be a leak in the cooling system, which allows coolant to escape and reduces its overall level.
Another reason could be improper maintenance, such as neglecting regular coolant checks or failing to replace them when necessary.
If you recently had repair work done on your vehicle that involved draining the coolant system but needed to refill it afterward correctly, this could also result in insufficient engine coolant.
#3. Defective Water Pump.
A defective water pump may result in inadequate coolant circulation throughout the engine.
The water pump plays a vital role in circulating the coolant from the radiator to the engine and back again, ensuring proper cooling. This circulation is disrupted when it malfunctions, leading to uneven coolant distribution and overheating.
#4. Old Engine Coolant.
Old engine coolant loses its effectiveness over time. The coolant becomes less efficient at absorbing and dissipating heat from the engine. This can result in the engine running hotter than average without reaching the point of overheating.
A low coolant level can also cause your car to run hot. If there isn’t enough coolant in the system, it won’t be able to properly regulate the engine’s temperature, leading to increased heat buildup.
#5. A Failing Engine Thermostat.
The thermostat regulates your engine’s temperature by controlling the coolant’s flow. When it starts malfunctioning, it may cause your car to run hotter than usual without reaching the point of overheating.
A common reason for a failing thermostat is age and wear. The metal components inside the thermostat can become weak or corroded, leading to improper functioning. Exposure to extreme temperatures and harsh conditions can also contribute to its deterioration.
Another factor that can cause a failing thermostat is debris or rust buildup within the cooling system. This buildup restricts proper coolant circulation and can prevent the thermostat from opening and closing as it should.
#6. A Defective Cooling Fan.
The cooling fan plays a vital role in regulating the engine temperature by pulling air through the radiator to dissipate heat. If this essential component malfunctions, it can result in an overheated engine.
A worn-out or damaged motor can cause the cooling fan to stop working correctly. Constant exposure to high temperatures and vibrations can affect the motor’s performance, reducing functionality or complete failure.
#7. An Inaccurate Coolant Temperature Sensor.
An inaccurate coolant temperature sensor is the culprit behind this issue. This diminutive component is vital in monitoring your engine’s temperature and sending signals to the dashboard gauge.
If it malfunctions and provides incorrect readings, it can give you a false alarm by indicating that your car is running hot when it’s not overheating.
The reason for an inaccurate coolant temperature sensor is a buildup of dirt or debris on its surface. Grime can accumulate on the sensor, causing it to deliver erroneous readings.
#8. An Unreliable Oil Temperature Sensor.
The oil temperature sensor is responsible for monitoring the temperature of the engine oil and sending signals to the car’s computer system.
If this sensor malfunctions or becomes unreliable, it can cause inaccurate readings, leading to a false indication of high temperatures. It may trigger unnecessary warnings and alarms, causing drivers to panic unnecessarily.
How to fix cars running hot but not overheating?
If you notice the temperature gauge going up but the engine hasn’t started to overheat, your quick action can prevent problems. Here’s what we would do as professional mechanics.
#1. Read Trouble Codes.
Every modern vehicle comes equipped with a diagnostic trouble code system that tells you when something is wrong. At the first sign of trouble with anything electronic, such as sophisticated thermostats, a code will be set in the system.
You can read these codes with your compatible scanner. If you aren’t sure what the information means, take a look at our online trouble code library.
#2. Check The Coolant Level.
The next step is just as easy to do. Take a look at the coolant level and top it off if needed. Here are the steps you want to follow.
- Only check the coolant when the engine is cool.
- Look on the side of the coolant reservoir. There may be markings on the plastic showing you the levels.
- If the coolant reaches the “Full” mark, you don’t have to do anything else.
- If it is below this mark, carefully remove the radiator cap.
- Add just enough of the coolant to top it off.
Make sure you use the right coolant type and mixture for your vehicle or you could cause major damage.
#3. Flush and Bleed Coolant System.
To get any air out of the cooling system, you need to bleed it.
- Take off the radiator cap after the engine is cool.
- Insert a funnel into the radiator.
- Fill the radiator up with as much coolant as you can. Make sure you use the right kind.
- Once the coolant is stable and not moving, start the vehicle.
- Turn on the heat to its hottest setting and the fan on low.
- As the coolant levels drop, top off the system again.
- Confirm that there is heat coming from the cabin vents.
- Watch the temperature gauge to ensure the engine doesn’t overheat.
- Once the radiator is completely topped off and not going down anymore, shut off the engine and put the cap back on.
- Drive the vehicle to ensure the car doesn’t overheat.
- Once the system is cooled back down, confirm that there’s still enough coolant. Top off if needed.
If it was time for a coolant change anyway, you could also flush the system. This requires you to drain out the old fluid and refill it.
#4. Measure The Coolant Temperature Sensor.
With a multimeter, you can test the coolant temperature sensor. The sensor is usually located next to the thermostat.
It’s best to reference your factory service manual when checking these readings. If you get anything other than what’s recommended by the manufacturer, you may choose to replace the sensor.
#5. Diagnose Thermostat and Coolant Flow.
Start the vehicle and let it idle. Look through the radiator filler neck to see if there’s any coolant flowing. You shouldn’t see anything flowing at first because the engine hasn’t reached its operating temperature. If it is flowing, the thermostat valve is stuck open.
If it’s not flowing, continue letting the engine run until it reaches optimal temperature. Look through the radiator filler neck again and the coolant should be flowing. If not, the thermostat is in a stuck closed position and the temperature will continue to rise.
#6. Contact A Professional.
Working with the car’s cooling system is no easy task. Even with all of the experience we have, we still find some aspects of it to be complicated and confusing.
If you are unsure what to do or you would rather not deal with the repair yourself, talk to your local auto technician. Sometimes, it’s best to trust the professionals, especially since an overheated engine can lead to massive repair bills.
Safe Driving Practices During Overheating
When your car is running hot but not overheating, it’s important to practice safe driving habits to prevent further damage. Here are some guidelines to follow:
- Pull Over to a Safe Location: If you notice your car’s temperature gauge rising or other signs of overheating, safely pull over to the side of the road or into a parking lot. Choose a location away from traffic to avoid any accidents or injuries.
- Turn Off the Engine: Once you’ve pulled over, turn off the engine to allow it to cool down. Leaving the engine running may exacerbate the overheating issue and potentially cause more damage.
- Open the Hood (if safe): If it’s safe to do so, open the hood to help dissipate heat more quickly. However, exercise caution as the engine and surrounding components may be extremely hot. Do not touch any hot surfaces or attempt to remove the radiator cap.
- Do Not Add Cold Water: While it may be tempting to pour cold water into the radiator, it’s not recommended. The sudden temperature change can cause severe damage to the engine block. Wait until the engine has cooled down before adding coolant.
- Call for Assistance: If you’re unable to resolve the issue or if the overheating persists, it’s best to call for professional assistance. A mechanic can diagnose the underlying problem and provide the necessary repairs.
How To Prevent Car Running Hot But Not Overheating Issue?
A car running hotter than normal, but not quite reaching the overheating point, can still lead to problems down the road.
Here are some tasks you can to to avoid this issue.
#1. Coolant system flush.
The coolant in your car’s cooling system doesn’t last forever. Over time, it can become contaminated with rust, debris, and lose its anti-corrosive properties. This act is typically recommended every 2-5 years or a specific mileage interval.
#2. Radiator check.
Look for any external leaks, and check for blockages within the radiator core. Clean any debris, bugs, or leaves from the fins, as they can restrict airflow and reduce cooling efficiency. A damaged radiator may need repair or replacement.
#3. Hoses and clamps.
Regularly inspect all hoses for signs of wear and tear, and ensure clamps are tight and secure. Replacing worn hoses and clamps can prevent leaks and ensure proper coolant flow.
#4. Thermostat replacement.
A stuck-closed thermostat restricts coolant flow, causing the engine to overheat. Conversely, a stuck-open thermostat can prevent the engine from reaching optimal operating temperature. A faulty thermostat should be replaced promptly.
#5. Maintain proper coolant level.
The coolant level in the overflow reservoir should be maintained within the specified range. Check it regularly and top it off as needed!
#6. Use the correct coolant.
Different coolants have different chemical compositions and are designed for specific engine types. Consult your owner’s manual for the correct coolant type for your vehicle.
#7. Monitor temperature gauge.
Make it a habit to regularly check your temperature gauge while driving. If you notice the needle consistently higher than its normal operating range, even if it’s not in the red zone, investigate the cause promptly. This early detection can prevent more serious issues.
#8. Minimize stop-and-go driving.
Stop-and-go traffic generates a significant amount of heat, putting extra strain on the cooling system.
When possible, try to avoid heavy traffic situations, especially during hot weather, to reduce the load on your cooling system.
#9. Address leaks.
Any leaks in the cooling system, no matter how small they may seem, should be addressed immediately.
Even a minor leak can eventually lead to significant coolant loss and overheating. Don’t delay in getting leaks repaired.
FAQs.
Q: What will cause an engine to run hotter than normal?
Several factors can affect the temperature balance of the engine of your vehicle. You have to properly check for the cause before you start any repair procedure.
This problem can be due to a low coolant level in the radiator, a faulty thermostat, a bad radiator, a damaged head gasket, a faulty water pump, or it might just be a bad temperature sensor or gauge giving a false reading.
Q: How to know if my engine is damaged from overheating?
There are several warning signs that can notify you when the engine of your vehicle begins to overheat. Paying attention to these signs would help safeguard your engine from further damage.
Most of the signs you will experience include: noise from your engine, an increase in the level of the temperature gauge, white smoke from the engine, odor from your vehicle’s engine, leakage of coolant under your vehicle, and low engine efficiency.
Q: How do you cool down an overheated car?
- To successfully reduce the temperature of your car when it overheats. You have to pay attention to the following steps:
- Put off the air conditioner of your vehicle.
- Turn the heater ON so that it can reduce the temperature of your engine by blowing the excess heat from the engine into the car.
- Park your vehicle in a safe area or put it in Neutral mode. This will assist in increasing the efficiency of the cooling system of your vehicle.
- You should open the hood or bonnet of your car to release the steam from the engine. But to do this, you have to be very careful.
Q: Why is my car randomly overheating?
A damaged radiator, low-quality coolant or low level of coolant in the radiator, a faulty radiator cap, a bad radiator fan, air bubbles in the cooling system of your vehicle, a damaged thermostat.
Or a broken are all the factors that can cause a high increase in the temperature of your vehicle.
Q: How long can a car run hot before damage?
Once your temperature gauge has indicated that your vehicle’s engine has gotten to a high level of hotness indicated while driving the car, you have just a few minutes before severe damages will be done to your vehicle.
That’s why the best option is to stop your car and investigate the problem immediately if you notice any sign that reflects a significant increase in the temperature of your vehicle’s engine.
Final Words
You need to understand that the engine is the heart of a vehicle. Therefore, the state of your vehicle’s engine should be of utmost importance to you.
Always check the various components of your vehicle before you put on the engine to drive and make sure you run a maintenance schedule for your vehicle.
Doing this, to a large extent, can lower the chances of your vehicle developing issues that will cause the problem of your car running hot but not overheating or any engine problem at all.