Stinky smell when AC is first turned on

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2014 CX-5 Touring
I searched and read the other threads in this forum about how CX-5's are prone to mold/mildew in the AC system, particularly if recirculate is used, with Auto settings and all that.

Our 2014 Touring does NOT have automatic climate control, however, and the stinky smell from the vents only seems to happen for a few seconds up to about a minute when the AC is first turned on after the car has been sitting awhile, such as overnight.

Now it is true that we've been keeping the car set on Recirculate pretty much exclusively. But we've always done that on our other/previous cars, and it's never been an issue. So is the preferred fix to just use the Fresh Air setting most of the time, and maybe turn off AC a few minutes prior to destination and let the fan run for a few minutes? Any other possible fixes to help prevent stinky vents particularly when the car is first used in the morning?
 
When was the cabin air filter changed? I roll my windows down at every opportunity to get some circulation. On a hot day after getting in my car it stays down for 2 minutes or so.
 
Cabin filter changed a few weeks ago after we got the car. The one in there previously was NASTY.

I notice the smell most often after the car has been sitting overnight in the garage, so it's definitely not burning hot inside.
 
I searched and read the other threads in this forum about how CX-5's are prone to mold/mildew in the AC system, particularly if recirculate is used, with Auto settings and all that.

Our 2014 Touring does NOT have automatic climate control, however, and the stinky smell from the vents only seems to happen for a few seconds up to about a minute when the AC is first turned on after the car has been sitting awhile, such as overnight.

Now it is true that we've been keeping the car set on Recirculate pretty much exclusively. But we've always done that on our other/previous cars, and it's never been an issue. So is the preferred fix to just use the Fresh Air setting most of the time, and maybe turn off AC a few minutes prior to destination and let the fan run for a few minutes? Any other possible fixes to help prevent stinky vents particularly when the car is first used in the morning?

you have mold and mildew in your AC system, most probably the evap coils, you probably like to keep the cabin very cold with the recirculate active, problem is that creates a lot of condensation in the vents and evap coils on humid days, perfect environment for micro-organisms to start growing, this happens mostly in summer humid days.

good news is that it should be an easy fix, see my link on how to inject Kool-It into the system to kill the mold and mildew

https://www.mazdas247.com/forum/showthread.php?123856340-Unclog-a-c-drain-and-remove-musty-smell-easily

after that, try not to turn the air temp all the way down to 60F (this creates a lot of condensation) and always use fresh air, and try to turn off AC 5 minutes before your destination to air and dry out any moisture in the system.

There's also this Meguiar's product, sort of like a fogger, you close all your car windows and activate recirculate and turn your AC to full blast and pop this Meguiar's can, it fogs up the interior and goes thru the HVAC to kill the bacteria.

https://www.amazon.com/dp/ (commissions earned)
 
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Lots of video on YouTube about this. Scotty Kilmer has a simple and inexpensive solution using a Lysol product.
 
you have mold and mildew in your AC system, most probably the evap coils, you probably like to keep the cabin very cold with the recirculate active, problem is that creates a lot of condensation in the vents and evap coils on humid days, perfect environment for micro-organisms to start growing, this happens mostly in summer humid days.

good news is that it should be an easy fix, see my link on how to inject Kool-It into the system to kill the mold and mildew

https://www.mazdas247.com/forum/showthread.php?123856340-Unclog-a-c-drain-and-remove-musty-smell-easily

after that, try not to turn the air temp all the way down to 60F (this creates a lot of condensation) and always use fresh air, and try to turn off AC 5 minutes before your destination to air and dry out any moisture in the system.

There's also this Meguiar's product, sort of like a fogger, you close all your car windows and activate recirculate and turn your AC to full blast and pop this Meguiar's can, it fogs up the interior and goes thru the HVAC to kill the bacteria.

https://www.amazon.com/dp/ (commissions earned)

Thanks for the info and links. We do not have the automatic climate control system, so there's no temperature readout. But yeah generally in summer we keep the temp knob all the way at full cold, and run the AC on recirculate.

I've owned 3 other cars and driven many additional cars, and have never experienced this problem before. My Integra *always* stays on full cold/recirculate in summer. I recently recharged the system on the Integra, also, and still never had any problems with weird smells from the vents. Why is it such an issue on this car in particular?
 
Thanks for the info and links. We do not have the automatic climate control system, so there's no temperature readout. But yeah generally in summer we keep the temp knob all the way at full cold, and run the AC on recirculate.

I've owned 3 other cars and driven many additional cars, and have never experienced this problem before. My Integra *always* stays on full cold/recirculate in summer. I recently recharged the system on the Integra, also, and still never had any problems with weird smells from the vents. Why is it such an issue on this car in particular?

Sounds like your car's previous owner was in an unusual environment.
 
Update: have used Fresh Air exclusively the past 2 days instead of Recirculate, and haven't noticed much of any gross smell in that time, not since about Saturday morning. I'll keep checking and will likely still pick up some of that Kool-It cleaner product just to make sure the nasty stuff is gone.

Then again, we had a really mild weekend, so there wasn't a ton of moisture in the air to generate a bunch of condensate. Which is why I still want to use the cleaner stuff to be sure.
 
Update: have used Fresh Air exclusively the past 2 days instead of Recirculate, and haven't noticed much of any gross smell in that time, not since about Saturday morning. I'll keep checking and will likely still pick up some of that Kool-It cleaner product just to make sure the nasty stuff is gone.

Then again, we had a really mild weekend, so there wasn't a ton of moisture in the air to generate a bunch of condensate. Which is why I still want to use the cleaner stuff to be sure.

Lysol trick has also worked for me in the past, see video:

 
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