Is My Car Smoking When Heater Is On?

February 27, 2024

If you’re noticing smoke coming out of your car’s vents when your heater is on, it could be a sign that something is wrong with your car. Typically, this means your heater core is leaking and producing fumes or steam when you turn on the air conditioning or heat. But sometimes it’s a more serious issue, like overheating or an internal problem with your engine. In that case, you need to schedule service so a technician can use tools and diagnostic technology to find the source of the problem.

It’s a good idea to make sure your climate controls are set to recirculate the air before you turn on the heat. This will eliminate any fresh air that may have been sucked in from outside and help you narrow down the problem.

If the smoke smells like antifreeze it’s probably your heater core leaking. This happens because the air blowing through the heater passes over a hose that is filled with coolant. If the hose leaks you’ll notice a sweet scent and smoke from the vents.

You might be able to temporarily seal a small leak in your heater core by draining the current coolant and adding a water and sealant mixture. But the best solution is to get your heater core replaced, as this is a common problem that causes cars to overheat and smoke when turned on the heat. Luckily, it’s also usually an inexpensive repair. So, if you’re seeing white smoke when your heater is on, it’s time to book an appointment with a mechanic.


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