Why Do Car Windows Fog Up – Causes & Solutions

Why Do Car Windows Fog Up – Causes & Solutions

When your automobile window fogs up, it may be annoying. However, to avoid it, you must first understand why vehicle windows fog up in the first place.

Car fog may appear harmless but can produce reduced visibility, leading to deadly accidents.

In this blog post, Auffenburg CDJR of Herrin, serving Carbondale, IL, will discuss why car windows fog up, and we will provide some solutions to help you keep your windows clear.

What Causes Windshield Fog?

Fog on your windshield can occur for a variety of causes, including:


The movement of molecules is what causes heat. Warm air holds more moisture than cold air. Water gets heated when it is hot outside, turning into fog rather than a liquid. Warm air also has greater space between molecules, allowing water molecules to fit into this gap.

Surface tension:

Water molecules prefer to connect with other water molecules rather than something like glass, resulting in tiny droplets.


Damp, warm air hitting on your car’s cooler windshield causes condensation. This frequently occurs in the early hours of the morning.

In the summer, the most irritating aspect of automobile window condensation is that the fog is on the outside of the window. This means you’ll have to clean the glass from the outside, and if it begins fogging up while driving, you’ll have to slow down or stop.

Solution for window fogging in summer:

You can remove fog in a variety of methods. And while no one-size-fits-all approach will always work, few are more likely to succeed.

Turn on the wipers on your windshield. You may wipe away the moisture and see considerably clearer by just turning on your front and rear-window wipers. This technique lets you see the front and back windows, but it will not solve the problem with the side windows.

Reduce the temperature of your air conditioner or turn it off entirely. You can prevent fogging by balancing the temperature differential inside and outside your automobile. You can typically avoid condensation by not turning off your air conditioner fully.

Turn off the recirculating air function. Turning off your air recirculation will help you solve the problem once more.

Crank open the window. You can crack open a window to let some of the humidity out. However, this is not suitable in the scorching summer heat.

Use an anti-fogging spray. An anti-fogging car spray is an excellent option. You can apply the mixture to clean, dry, and degreased windows. The method works well, although only one application lasts 10-15 days.

Clean the windows and windshield. You can also clean your car’s window and windshield with an ammonium-based cleaner to prevent fogging.

Always ask your mechanic about leaks and malfunction. Auffenberg Chrysler of Herrin, serving Carbondale, IL, is the place to go if you need servicing for your Mopar vehicle, whether it’s a Chrysler, Dodge, or Ram.

We’ve got you covered, from routine maintenance to extensive repairs, including your engine and gearbox. Our crew can take care of everything your vehicle requires. Schedule your service today!