Back to all

That Vexing Vapor Venting (Vapor Coming out of Vents)

May 9, 2021

You may have noticed sometimes on a hot and humid day, vapor will come out of your vehicle's vents when you have the air conditioning on.  Is that something to be concerned about? Well, it depends.

Sometimes that steam or vapor can be caused by water accumulating in the vent system after it has condensed.  And sometimes water can pool at the bottom of a vent.  When you turn on the blower mower, the air hits the water and may create steam or vapor that you can see in the cabin.

One thing to check is if that vapor smells like anything.  If it doesn't, that's a good sign. You may be able to run the fan for a while and the issue may just go away when things dry out.  But moisture collecting in the ventilation hoses in a hot vehicle may be a breeding ground for mold, and that can have health consequences.

There's another possibility. Ventilation systems often have drains to get rid of any accumulated water, and debris can sometimes clog them.  A technician can clean out those drains and you'll be back in business.

One thing to nose around for is a sweet smell coming out of your vents.  Sometimes the heater core (a component of your vehicle's heater system) can develop very tiny holes.  That sweet smell may be coolant that's been vaporized by those tiny holes entering your cabin. 

It's always a good thing to mention to your service advisor any abnormality you're seeing—or smelling—in your vehicle.  By venting a little about your vents, a technician can get to the bottom of the problem before it starts "clouding" the issue.

Tuffy Walled Lake
784 N. Pontiac Trail
Walled Lake, Michigan 48390
248.624.4440

Need Service?

More articles from Tuffy Tire & Auto Service Center Walled Lake

Don't Start with That (Bad Starter Motor)

April 27, 2025

We've all heard that expression, "That's a non starter." When it comes to your vehicle, that's not music to a driver's ears. That sickening sound when you start the ignition and instead of hearing the engine crank, you hear it slowly turn over and your dash lights go dim. There can be many reaso... More

Why did my vehicle fail its emissions test?

April 20, 2025

We all want to breathe clean air and keep our planet green. One of the ways to do that is by requiring all vehicles with internal combustion engines to pass an emissions test. Thats because these vehicles can be big polluters. Everyone wants their car to pass the test so they can continue the... More

Keeping Your Cool (Water Pump Replacement)

April 13, 2025

No matter what the temperature is outside, it's important for your vehicle's engine to remain cool, calm, and collected. Well, cool, anyway. If your vehicle has a gasoline engine, it's powered by a bunch of explosions involving spark plugs, pistons, gasoline, and air. And the by-product of all ... More