Even if you love the heat of summer, but you need to help your car keep its cool when temperatures rise. An engine that runs too hot can damage the vehicle and threaten your safety. Here are some tips we’ve compiled to help prevent your car from overheating:
What causes a car to overheat?
You might well ask, “Why is my engine overheating?” There are a few engine problems that can cause a car to run hot. High temperatures alone might not be causing your vehicle to overheat. If your car’s coolant systems aren’t functioning correctly, that can lead to serious damage to your engine and expensive repairs. Here are a few reasons why your car may be running hot:
Coolant system malfunction
Every car has a coolant system to help keep the temperature of the engine down. If your coolant system has a leak, blockage or pump malfunction, the coolant might not be able to circulate properly.1 Coolant system malfunctions aren’t just problematic when it’s hot out; very cold temperatures can cause the coolant to freeze and prevent circulation.
Broken temperature gauge
Another possible issue could be a problem with the thermostat. A vehicle’s temperature gauge is responsible for regulating the amount of coolant flowing through the engine. A broken or malfunctioning gauge can easily cause your car to overheat.
Low motor oil
Motor oil does more than just lubricate moving parts. It also helps to remove excess heat from the engine. If your vehicle has low oil, it might be causing your car to run hot.
If your cooling fan isn’t turning on or running at the right level, it can cause your car to overheat. Radiator fans usually run on electric motors, so any motor mechanical problems can lead to your fan not providing enough cool air flow.
Of course, these aren’t the only problems that can cause a car to overheat. It’s a good idea to find a reliable mechanic who can diagnose and service your car and get protection in case your car overheats while you’re on the road.
What happens when a car overheats?
Cars can give off several kinds of signals that they are overheating, including:
- Steam coming from your car’s hood
- A strange burning or sweet odor coming from the car’s engine
- The engine temperature gauge on your dashboard spiking into the red or to “H”; Note that engine temperature gauge symbols can vary from car to car.1
What to do when your car overheats
If you find that your engine has overheated follow these steps to ensure that you and your vehicle remain safe:
- Pull over to the side of the road, park your car and turn off the engine as soon as possible. Let your car cool for a minimum of 10 minutes.1
- Open the hood of your car to allow the heat to dissipate quickly.1
- Once your car has cooled off, turn the ignition to its first position (don’t start the engine). If you see that the temperature gauge is within a normal range and engine fluid levels are sufficient, try to start the engine.1
- If the engine makes unusual sounds or it does not start at all, it’s best to stay on the safe side and call for roadside assistance to have your car towed. This will allow for a mechanic to inspect it and inform you of the necessary repairs.1
How to keep your car from overheating
You might love the heat of summer, but you need to help your car keep its cool when temperatures rise. An engine that runs too hot can damage the vehicle and threaten your safety. Here are some tips we’ve compiled to help prevent your car from overheating.
- Park your car in the shade.
Parking in the shade not only keeps you cool but can also prolong the life of your car. No shady spot? Use a sunshade to reduce heat inside the car.2 You can feel the temperature difference between the shade and the sun and so can your car.
- Use car window shades.
Keeping window shades in the car is helpful because you can’t always guarantee that you’ll find a shaded or covered area to park in. These UV heat shields keep the interior from getting too hot, plus they protect your interior from the damaging effects of the sun.2 You might even consider getting custom-made window shades to fit your car’s make and model. These shades can be more effective at keeping out all the rays.
- Tint your windows.
A local dealership or auto body shop can apply window tinting or window film to help keep your car cooler and provide UV ray protection against sun damage.2 Just be sure to research window tinting laws and guidelines where you live.
- Leave car windows open slightly.
Closed windows trap hot air and the glass serves as a conductor that helps heat up the enclosed space. Leave your windows open slightly so the air can escape – and if you have a sunroof, crack that open too.2 Make sure the opening is not large enough for someone to reach through. If you leave your windows cracked, remember to keep an eye on the weather; one sudden summer storm could lead to a soggy interior.
- Turn the floor air vents on.
Most people get in the car and turn the dashboard vents on “high” to get the air flowing. But you’re actually better off directing the air through the floor vents. Hot air rises, so switch to the bottom vents and put your blower on the maximum setting to push that air out. Then, once the car begins cooling, you can open the upper vents again.3
- Use the fresh air setting instead of recirculation on your A/C.
Set your air conditioning on fresh air for about 10 minutes. Using the recirculation setting means you’re just moving that hot, trapped air around your vehicle, so that’s something you’ll want to use after your car has had the chance to cool down.
- Keep your eye on the engine temperature gauge.
Located on the dashboard, your engine temperature gauge has a needle that should always be pointing toward the center. If it points toward hot, pull over in a safe area, turn off the engine and let the car cool down. Leather or dark upholstery can get especially hot in the sun during the summer. You can keep your car’s interior cooler by covering your steering wheel and seats with a towel, a blanket or seat and steering wheel covers.2
- Turn on the heat to cool the engine.
Turning on the heat might be the last thing you want to do on a hot summer day, but it can pull hot air from the engine compartment and cool the engine. It won’t fix the underlying problem, but it’s a good measure for long drives until you can have the car inspected and repaired.3
- Add engine coolant.
To check the coolant level, open the hood and locate the coolant reservoir. The coolant level is shown by indicator lines on the reservoir. If too low, simply add the appropriate amount of coolant and reattach the cap. Engine coolant is often sold as a 50/50 mix of water and coolant. You can also buy concentrated coolant and mix it yourself.1
Safety tip: Never add coolant to a hot engine. Wait for the engine to cool before removing the cap or pouring in coolant.
- Have your radiator flushed by a mechanic.
A radiator flush, also known as coolant flush, involves draining old coolant from the radiator, cleaning it with flush fluid and adding new coolant. Mechanics recommend a flush every 40,000 miles, but check your owner’s manual for the manufacturer’s recommendation.1 Even if you keep engine coolant at the right levels, it will eventually get dirty and need to be replaced.
- Consider replacing your car battery.
If your car battery is older than 3 years, it might not be providing the power it once did, so your car has to work harder and can overheat. Your mechanic can help you determine whether you need a new battery. Learn the signs your vehicle may need a new car battery.
 “What to Do (& Not Do) When Your Car Overheats,” firestonecompleteautocare.com/blog/maintenance/when-car-overheats (Accessed July 22, 2019 and March 23. 2022).
 “How to Stop Your Car’s Interior From Overheating,” Justin Smith, breakerlink.com/blog/driving/how-to-stop-your-cars-interior-from-overheating/ (Accessed July 8, 2019 and March 23, 2022).
 “How to Avoid Overheating Your Vehicle,” ormsbyservice.com/how-to-avoid-overheating-your-vehicle (Accessed July 22, 2020 and March 23, 2022).
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