Condensation Fog inside windshield

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Deuce16GMCs

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Started noticing that when it rains followed by heat (in Florida) the 23 Tahoe has started develop a foggy interior windshield.

Is interior fogging normal or am I to assume there's water getting into the truck.

There's nothing wet on the headliner, a-pillars, floor boards, etc. There's no moisture smell or in the case of Florida, a mold smell.

It does rain heavily here in FL. Especially this year. Doors have been opened during rain and all weather mats have gotten wet, but not enough to trap moisture inside.

Surely, if there was a leak, after a massive rain strom, there would be a wet spot somewhere in the car.

Any ideas? Or just normal?
 

swathdiver

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Started noticing that when it rains followed by heat (in Florida) the 23 Tahoe has started develop a foggy interior windshield.

Is interior fogging normal or am I to assume there's water getting into the truck.

There's nothing wet on the headliner, a-pillars, floor boards, etc. There's no moisture smell or in the case of Florida, a mold smell.

It does rain heavily here in FL. Especially this year. Doors have been opened during rain and all weather mats have gotten wet, but not enough to trap moisture inside.

Surely, if there was a leak, after a massive rain strom, there would be a wet spot somewhere in the car.

Any ideas? Or just normal?
This is the time of year when my windows are always fogged up. There's near 100% humidity outside and 90+ degrees, and my AC is set to 68 degrees. I have to run the wipers to clear the condensation off the glass and even clear the side windows by lowering them a time or two while driving in the neighborhood. Normal.
 

swathdiver

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Started noticing that when it rains followed by heat (in Florida) the 23 Tahoe has started develop a foggy interior windshield.

Is interior fogging normal or am I to assume there's water getting into the truck.

There's nothing wet on the headliner, a-pillars, floor boards, etc. There's no moisture smell or in the case of Florida, a mold smell.

It does rain heavily here in FL. Especially this year. Doors have been opened during rain and all weather mats have gotten wet, but not enough to trap moisture inside.

Surely, if there was a leak, after a massive rain strom, there would be a wet spot somewhere in the car.

Any ideas? Or just normal?
Oh, to deal with potential mold in the evaporator, I activated a feature on my generation of trucks called Afterblow. Under certain conditions, it runs the blower motor to dry out the evaporators at low speed for a while to prevent that moldy smell. Not sure if it's a feature on yours but worth asking next time it's in for service. It has to be turned on with dealer level scan tool; at least on mine.
 
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Deuce16GMCs

Deuce16GMCs

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This is normal, after rain in the cabin there is moist air that condenses on the windows.
Yeah. It's literally only happens if the truck sat parked out in the heat, then it rained.

The rain cools the truck, and the interior of the window gather condensation. Which tells me that there's moisture or humid air inside the truck.

Glad to hear it's normal humid air and not a water leak somewhere especially after the dealership did work to the firewall of the Tahoe.
 

Vladimir2306

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Yeah. It's literally only happens if the truck sat parked out in the heat, then it rained.

The rain cools the truck, and the interior of the window gather condensation. Which tells me that there's moisture or humid air inside the truck.

Glad to hear it's normal humid air and not a water leak somewhere especially after the dealership did work to the firewall of the Tahoe.
Just to insure))) from the experience of past Tahoe models. Try moving the doors. Open them and close them. If you suddenly hear gurgling in one of them, then it is possible that there is water in the door, in order to remove it, you need to slightly move the rubber sealing the bottom of the door. It’s just that during rain, water flowing down the glass flows inside the door, and flows out from below through the drain, it happens that it gets clogged, and 5 liters of water collects in the door)))
 

ExEl03X4

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In thirty years, I have only seen this happen when there is water inside the car. Do a thorough check under the carpet and pads. Make sure the a/c evaporator drain tube is not clogged. If you use the defrost mode it won't take long to dump a lot of water inside.
 

Doubeleive

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In thirty years, I have only seen this happen when there is water inside the car. Do a thorough check under the carpet and pads. Make sure the a/c evaporator drain tube is not clogged. If you use the defrost mode it won't take long to dump a lot of water inside.
you must live somewhere with virtually no humidity, some places you cannot prevent it from happening, it's just science.
 

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