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Q & A: evil spirits fogging car?

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Most recent answer: 04/11/2013
Q:
I was driving with AC on muggy day with clouds,and within an instant ever single window of my car was foggy (I could barely see out of them). The cars windows around me weren't fogged up. I drive a 2009 and I bought it brand new. It happened to me once before in 1996. My huband bought me a car on a friday (brand new) and that sunday the same thing happened all windows fogged up (of course on monday, I returned the car and ask for a different one. I felt like an evil spirit was in that car.
- Sandra (age 54)
Lafayette, LA
A:
In my experience most cars have evil spirits at times, but I try not to judge them unless it gets persistent. In fact, this applies to most machines. Just yesterday my microwave oven went on when I opened the door! It seemed like an unprovoked attack, but who knows what experiences it had been through recently?

Here's what sounds likely to have been going on with your car. Obviously the air was nearly saturated with water. Turning on the AC starts to cool it, leaving it super-saturated. That means water will condense out onto something. Usually the cold AC coils pull enough water out of the air to leave it reasonably dry, but they may not have been able to handle all that moisture. Since visibility is more important than short-term comfort, one thing to do in this situation is to temporarily turn on the heat with the AC also on. The cold coils will pull water out and the heater will keep the rest warm enough not to be quite saturated. It's not energy-efficient, except when compared to a car crash.

Mike W.

(published on 04/11/2013)

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