Q: Air conditioning smells bad when car enables autostop feature

asked by on May 12, 2016

I am noticing a musty, foul smell from my air conditioning when the auto stop feature is enabled on my car. I have noticed that the air doesn't stay as cold, but while the air is blowing and also right after the car starts back up (after stopping), the air smells musty. Then, the smell goes away until the autostop enables again. My car has about 6,000 miles. Could this be the cabin air filter?

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Your vehicle is new enough that I couldn’t find much information on the air conditioning system. I’m guessing your vehicle probably has a dual scroll AC compressor in which one scroll is driven off the engine and the other is electric. In order to prevent lack of cooling at idle, this design is used in hybrids and vehicle with start/stop ability. So, the lack of cooling may be due to a problem with this system. The foul smell by be result of bacteria accumulating on the AC components. Replacing the cabin filter may help with this problem somewhat. I suggest you have a trained professional diagnose your vehicle firsthand to determine the exact cause of the smell.

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