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Q: I have a terrible smell coming out when I turn on my fan. What could this be?

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When I turn my fan on, either heat or air, a terrible smell comes out. What could this be?

My car has 139000 miles.
My car has an automatic transmission.

Hi, thanks for writing in. This is often times related to your cabin filter. This is a paper filter that filters the air as it comes into the cabin from the outside of the car when turning on any of the vents whether it be for air conditioning, heat or defrost. This is very similar to the air filter for your car’s engine. This should typically be changed at the same time your engine air filter is changed (about every other oil change or so - depending on how dirty gets). When this filter gets dirty, it can generate an awful smell that will circulate throughout the cabin in the car. If you would like help with this replacement, consider having an expert automotive technician from YourMechanic come to your home or office to perform the replacement for you.

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