Are You Suspecting That Your Heater Core May Be Failing?


Here are 5 common signs that indicate that your vehicles heater core may need to be serviced or repaired.

To learn more about how the heater core works, click here.

1. Your Heat Is Not Working

This one may seem like a no brainer, however, the problem could be in another part of the system, such as a fault blower motor, electrical issue, etc. If all other components test good, there is more than likely a clog in the system, a leak, or a tear or hole in the heater core. A hole can allow the warm air to escape before it gets to the cabin. Typically, if it’s only a small hole you’ll barely feel a difference, but if it’s larger you’ll likely be experiencing a chilly blast of cool air. If the system is clogged, you may experience an overall decrease in available heat inside the cabin.

 2. Your Windows Are Fogging Up

The most common sign of a heater core problem is when the inside of your vehicle suddenly fogs up, covering all the windows with condensation. What happens is the warm coolant leaks into the cabin of the vehicle, causing fog as it evaporates into steam when it hits the cooler air inside your car.

3. The Air In Your Car Smells Sweet

Even if the windows aren’t foggy and your heat seems to be working, when your heater core begins to break down you may smell a sickly-sweet aroma in your car. This is the smell of coolant and a sure sign that radiator fluid is leaking. You might even smell it outside your car. If this happens, check underneath your vehicle for leaks as well as inside the cabin on the passenger side of the vehicle, where the heater core is typically located.

4. Your Car Has Become Extra Thirsty

If you suddenly realize that you’re going through an excessive amount of coolant, this may be another sign of a leak somewhere in the system. If you’re not sure where the leak is, check your passenger side floor first. It might be escaping right into your cabin and instead of creating fog, it forms a puddle right on the floor.

5. Your Car Is Overheating

This may be a problem with the entire cooling system in your vehicle, which includes the heater core. While your radiator could be the culprit, there are other parts of your engine that can cause it to overheat. Extreme heat is a serious problem for major components in your vehicle’s engine and without proper maintenance, catastrophic failure can occur. If your vehicle is overheating, DO NOT drive it and have it towed immediately to your nearest auto repair facility.