Here are the top 9 reasons for car overheating. Click on each one to learn more and discover what you should do to fix it.
You may also be interested in our "Tips to Prevent Your Car from Overheating".
If you need a mechanic you can trust to take a look at your vehicle, contact us.
Discover the top reasons for car overheating and what to do
Top 9 Reasons for Car Overheating
1. You have too little or no coolant
Your car's engine produces a lot of heat when it is operating. Coolant is a liquid that helps to keep your engine cool and prevents it from overheating. If you have too little or no coolant, your engine can easily start to overheat, especially if you are sitting in traffic or stopped for an extended period of time like at a red light or in construction.
What You Should Do:
Pull over when it is safe to do so and let your engine cool down before trying to check your coolant level. You should wait at least a couple of hours after you've turned off your engine before you try to remove your radiator cap.
This is because your coolant is under great pressure when it is hot, so if you try to remove the cap, you can get severely burned from the scalding hot coolant and steam that will burst out when the cap is removed.
Once your engine is cool, you can lift your hood, remove your radiator cap and coolant reservoir cap to see how much fluid you have. Follow the labels on your coolant reservoir to see how much to add.
The following video will show you how to check your coolant level.
Learn how to check your car’s coolant level
2. You have a leaking, blocked, or ruptured coolant hose
Over time your coolant hoses can get damaged or simply wear out. If this has happened then you could be losing coolant where it is leaking or if you have a block in your hoses, then your coolant won't be able to circulate properly through your cooling system.
What You Should Do:
If your coolant hoses are damaged or blocked they will need to be replaced or unblocked. Unless you are comfortable with this type of repair, it is best to get a professional to do this for you.
The following video will show you how your vehicle's cooling system works.
Your cooling system circulates coolant in your vehicle
3. Your belts are worn out
Another one of the top reasons for car overheating is belts that are worn out. If the belts in your coolant system are worn out or frayed then they won't be able to maintain proper airflow to help keep your engine cool.
What You Should Do:
Inspect or have your belts inspected to see if there are any signs of wear or damage. If so, then they will need to be replaced.
4. You have a broken water pump
Your water pump is another important component in your car's cooling system. If your car's water pump gets cracked or starts to leak, it won't have the right pressure to move coolant through your system to cool your engine and it will start to overheat.
What You Should Do:
You will need to get your car's water pump replaced.
Learn how a water pump works
5. Your radiator is cracked or leaking
The job of your radiator is to pull heat out of your engine. If it has a crack or a leak, it won't be able to properly remove this heat and your car will start overheating. You can tell that you have a problem with your radiator if:
Your car temperature gauge goes higher than normal
You are leaking coolant
Your radiator fluid has changed colour and it looks rusty. It will eventually turn into sludge.
What You Should Do:
You can temporarily fix a leak in your radiator by adding a product such as "Bar’s Leaks" to it. This may fix your leak in the short term, however, you will eventually need to replace your radiator.
The following video shows what is involved in replacing a radiator. If you would like a professional to do this for you, contact Hansma.
Radiators pull heat away from your car’s engine
6. Your radiator fan is broken
A broken radiator fan is another one of the top reasons for your car overheating. A radiator fan draws air across your engine's radiator which helps keep your engine cool. When it is working properly, it can effectively help to keep your engine cool even if you are stopped or the temperature outside is extremely hot.
Here are some signs that could indicate that your radiator fan is broken:
Your temperature gauge goes up when you are driving slowly or idling
You have a blown fuse in your vehicle's use panel
You hear a noisy fan sound
What You Should Do:
If your radiator fan is broken, you will need to get it replaced.
Source: Holley
A broken radiator fan is another one of the top reasons for car overheating
7. Your radiator is clogged
If your radiator is clogged up your car may overheat. Rust can build up over time inside your radiator especially if you don't get regular radiator flushes. In addition, if you use a poor quality coolant, it may contain contaminants that could clog your radiator. A clogged radiator will prevent coolant from flowing properly to do its job of cooling your engine.
What You Should Do:
Have your radiator checked out. It may need to be flushed and you may need to purchase a better quality coolant.
Your radiator may need to be flushed
8. You have a low engine oil level
Another one of the top reasons for car overheating is having a low engine oil level. Your motor oil helps to stop your car from overheating by minimizing the friction in your engine. If your engine oil level is low, then your car may overheat.
What You Should Do:
Regularly check your engine oil level and fill it up when necessary. If you are going through engine oil very quickly and you notice oil stains under your vehicle, then you may have a leak and you will need to get this fixed.
The following video will show you how to check your engine oil.
Check your engine oil to make sure the level is okay
9. Your thermostat is broken
The last of our top reasons for car overheating is a broken thermostat. Your thermostat controls the flow of coolant in your system based on the temperature of your engine. If the temperature is hot, more coolant is released and vice versa. If your thermostat is broken, then you might find that your car is overheating.
What You Should Do:
You will need to replace your thermostat. This is a relatively inexpensive and common repair when done by a mechanic you can trust.
Your thermostat regulates the amount of coolant flow
Tips to Prevent Your Car from Overheating
Here are a few regular maintenance tasks that you can do to help make sure that your engine doesn't overheat. These include:
Refill or top off your coolant levels as soon as they fall below the manufacturer's recommended level. If your coolant reservoir is empty, you should use a mix of 50/50 antifreeze/coolant and water.
Keep an eye on your car's thermostat while you are driving.
Don't overuse your air conditioning system on really hot days.
Have regular coolant flushes and exchanges done.
Have your radiator checked and maintained as often as suggested by your car’s manufacturer.
Hansma Can Help if Your Car Is Overheating
If your car is overheating, contact Hansma Automotive. Here are the reasons why:
Over 33 Years of Service: We've been serving the Waterloo region with the highest quality automotive services since 1987.
Locally Owned and Operated: You can feel good about supporting a locally owned and operated family business.
True Customer Care: At Hansma, we truly care about our customers. We will do our best to provide you with great customer care and service. When you come to Hansma, you'll be treated like family.
Honest Customer Service: Our customers have come to appreciate our honest service. Our word-of-mouth referrals continue to be our largest source of new customers.
Competitive Pricing: Whether you are looking for the best tire change Kitchener has to offer or you require one of our other automotive services, our highly trained technicians will be able to diagnose and fix your vehicle at a highly competitive price.
Reliable Repairs: You can rely on the technical expertise of our friendly staff to keep your vehicle in peak condition.
Contact us today to book an appointment.
What Our Customers Think of Our Service…
“These folks are amazing. They are helpful, knowledgeable, friendly, and they get your vehicle taken care of fast and correct. And their prices are more than reasonable. I found this place by accident and I tell ya, I won’t go anywhere else anymore. They are my ONLY vehicle place. Highly recommend.”