As fall turns into winter, a lot can arise with your vehicle. You might have experienced a dead battery, or noticed balding tires make your car slide a bit more. But did you know that your car can overheat in winter too?

It seems counterintuitive. If it’s cold outside, why would your engine run hot? But it’s a very real possibility if your vehicle isn’t in good working condition. 

Before the temperature gauge starts climbing, and your car’s engine starts giving you problems, learn some easy troubleshooting methods to avoid your car overheating. 

What Causes Cars To Overheat In The Winter?

Now that you know your vehicle can overheat in the winter, let’s start there. This is what causes an engine to overheat, no matter what the temperature gauge reads. 

Low Coolant Levels: Even in freezing temperatures, your car’s engine generates a tremendous amount of heat. Coolant, or antifreeze, is responsible for absorbing that heat and keeping the engine temperature in check. If you’re running low on coolant, the engine doesn’t have enough of it to do the job, and things can heat up fast—even in the dead of winter. Always check your coolant levels before the season changes!

Thermostat Issues: The thermostat acts like a gatekeeper, opening and closing to let coolant flow through the engine as needed. If it sticks shut, your engine can overheat because the coolant isn’t circulating. It doesn’t care if it’s -10°F outside; if the thermostat is malfunctioning, the engine can still boil over. You might notice erratic temperature gauge readings or slow cabin heating when the thermostat is on the fritz.

Clogged or Damaged Radiator: The radiator is essential for cooling, as it allows heat to escape from the engine. If it’s clogged with debris, dirt, or rust, or if there’s damage from a stray rock or corrosion, the coolant can’t circulate effectively. Winter doesn’t make this problem go away—it just hides it under a layer of snow! Keep your radiator clean and ensure it’s in good shape before winter hits.

Water Pump Problems: The water pump pumps coolant through the system. When it fails, the coolant can’t circulate, which leads to overheating, even in the chilliest weather. You might hear odd whining noises, see coolant leaks, or experience fluctuating engine temperatures—these are all red flags that your water pump may be going bad.

Blocked Heater Core: The heater core not only warms up your cabin in winter but also helps maintain proper engine temperatures by transferring heat from the engine coolant. If it becomes blocked or corroded, coolant flow is restricted, and your engine can overheat. You might notice poor heating performance inside the car or foggy windows—both signs that something’s up with your heater core.

Frozen Coolant: Yes, this is a real thing! If you haven’t used the right mixture of antifreeze and water in your cooling system, the coolant can freeze in extreme cold. When this happens, the flow of coolant stops completely, leaving your engine to overheat. It’s like putting a lid on a boiling pot—the heat has nowhere to go. Always check that your antifreeze is winter-ready!

Radiator Fan Failure: Even in winter, your radiator needs airflow to cool the engine. The radiator fan pulls in air to help the radiator cool down the coolant. If the fan isn’t working properly, it’s like trying to cool down without a breeze—you’re bound to overheat. Pay attention to any strange noises or if your engine starts running hot while idling.

What Causes Cars To Overheat In The Summer?

Winter, spring, summer, and fall, your engine can be at risk if it overheats. But the heat of the summer has some risks that aren’t the same when the temperatures fall below freezing. 

Low Coolant Levels: Coolant is hydration for your vehicle. In the blazing heat of summer, your engine needs plenty of it to keep its cool. If you’re running low on coolant (a mix of antifreeze and water), the engine can’t shed the extra heat it builds up, leading to overheating. It’s like running a marathon without drinking water—you’re going to overheat eventually!

Faulty Thermostat: The thermostat only lets coolant in when things get too hot. If the thermostat gets stuck closed, it won’t allow the coolant to circulate, and the engine will overheat quickly, no matter how much coolant you’ve got. A faulty thermostat might even leave you sweating it out on the side of the road, so keep an eye on your temperature gauge.

Leaking or Clogged Radiator: Your radiator is essential in keeping the engine’s temperature down by dispersing heat. However, if it’s leaking or clogged with dirt, debris, or rust, it can’t do its job effectively. In the summer heat, this can spell disaster. Imagine trying to cool off under the sun, but your fan is broken—that’s what your engine feels like when the radiator isn’t working properly.

Water Pump Failure: The water pump keeps coolant moving through your engine, ensuring it stays at a healthy temperature. If the pump isn’t working (due to wear, leaks, or belt issues), coolant can’t circulate, and the engine will overheat. You might hear a high-pitched whining sound or notice coolant leaks if the water pump is failing.

Broken or Failing Radiator Fan: In hot weather, your radiator fan works overtime to pull cooler air through the radiator, especially when you’re stuck in traffic. If it’s broken or not spinning fast enough, your engine will start to run hotter. Without that airflow, the heat just sits there, causing the temperature to rise rapidly, especially in those bumper-to-bumper summer traffic jams.

Air Conditioning Overload: Your air conditioning works hard to keep you cool in summer, but it also puts extra strain on your engine. Running the AC for extended periods in extreme heat adds to the load on your cooling system. This can push your engine’s temperature higher, especially if other cooling components aren’t working at full capacity. Eventually, something’s going to give.

Old or Damaged Hoses: Your cooling system relies on a series of hoses to move coolant around the engine. Over time, these hoses can crack, develop leaks, or simply wear out. In hot weather, weak hoses are more prone to failure. If a hose bursts or leaks, coolant won’t reach your engine, causing the temperature to rise. 

Radiator Cap Issues: That little radiator cap actually plays a big role in keeping your car’s temperature in check. It maintains the pressure in your cooling system, ensuring coolant circulates properly. If the cap is worn or not sealing right, the pressure drops, coolant can boil over, and your engine will overheat. A faulty radiator cap might seem small, but it can lead to big problems under the hood in the summer heat.

Is Your Car Overheating? 

Do you see your car problems anywhere here? It might be time to bring your vehicle in and have it checked out. 

Even something that seems minor can cause significant damage if it impacts your car’s engine. We can help you with that. We’ll get to the root of the problem, fix it, and have you back on the road in no time. 

How can we help you with your vehicle?