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Q: AC smells really bad, what can I do?

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There is a bad, moldy odor every time the A/C is turned on in our 2012 Camry LE (2.5L automatic, 82k miles). The kids are embarrassed to have their friends ride in the car. My husband and I are worried it could actually make us all sick. What's wrong with the A/C?

A: Bad smells are not fun! It sounds to me lik...

Bad smells are not fun! It sounds to me like we may have a clogged A/C drain on our hands. When the air conditioner is being operated in your vehicle, just like ice water in a cold glass, condensation drops will begin to form on the evaporator. While the A/C drain is supposed to allow this condensation to exit, it does happen where sometimes pieces of debris can get caught inside and block this passage of water. Its this trapped water in the evaporator box that is often the culprit for a musty type of smell. When left untreated, this water can overflow and escape the evaporator box, draining onto floorboards and soaking carpets and floor mats. To tackle this smell, your first step will be to have a certified mechanic inspect the A/C drain for any debris blocking the drain. You will also want to check for dampness in the floorboards to make sure the smell is not coming from them. More often than not, the procedure is as simple as unclogging the drain and removing any excess water from the evaporator. However if the carpets turn out to already be damp, a wet/dry vacuum should be used to remove as much of the water as possible. A trick I have learned over the years involves placing black and white newspaper pages between the carpet and the floor mats for up to two days to help absorb any moisture that could not be removed with the vacuum. If the smell remains after all of these steps have been tackled, then the carpets may need to be removed by a professional, inspected for mildew or mold, and replaced.

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