Back to all

That Vexing Vapor Venting (Vapor Coming out of Vents)

September 29, 2024

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.

Top Tech Auto Repair Clawson
664 S Rochester Rd
Clawson, Michigan 48017
248-589-0980
http://www.toptechautorepairclawson.com

Need Service?

More articles from Top Tech Auto Repair Clawson

A Clean Start (Battery Cleaning)

December 21, 2025

You may be fanatical about keeping the outside of your vehicle clean. But what about what's under the hood? Have you ever thought about how dirt and grime may be affecting your engine's components? One of the most important parts under your hood to keep clean is your vehicle's battery. With a d... More

The Sign of the Shield (Heat Shield Repair and Replacement)

December 14, 2025

Even in the months where temperatures are cooler, heat is still an enemy of your vehicle. When your engine runs, it creates heat, so there are numerous heat shields that protect other parts from those higher temperatures. Heat shields are installed around several areas of the exhaust system. Ot... More

The Light Nobody Wants to See (Check Engine Light)

December 7, 2025

You've probably had your Check Engine Light go on. Then it goes off and you figure, hey, whatever the problem was, it's gone now and I don't have to worry about it. Well, the problem may have gone away and it may not have. Your vehicle likely has one of these warning lights on the instrument pa... More