Bad smell when air is on but ac off
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2019 E 450, 2016 E350 4matic (retired), 2018 Ford Edge Sport, 2008 Porsche Boxster
Hope this helps
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From: Fleriduh
W212 E63S Wagon - GSL580 - E63 - E350 - C300
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2022 GLE 350 & 2024 E 450
The smell was occurring when the AC was off or when the start/stop engine turned off the AC. I ran the air without AC yesterday on high for about 5 minutes and eventually the smell went away. Will try again to see if it comes back!
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2024 EQE 500
It used to be that with MB, always have Auto turned to on. Or, run the AC for the last few miles of driving. This dries out the condenser helping to minimize mold growth.
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From: Tennessee
W214 E450
You should leave the AC on and Ideally, leave it on auto. The car will then manage the system based on the set temp. You are probably causing moisture in the system that is turning moldy. Worse than the smell is the fact you may be breathing mold which is not good for your health.
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You should leave the AC on and Ideally, leave it on auto. The car will then manage the system based on the set temp. You are probably causing moisture in the system that is turning moldy. Worse than the smell is the fact you may be breathing mold which is not good for your health.
Having said that, when the temps are below 70 degrees I turn the AC off. Basically from October through the end of April my AC is off: exception when it rains or other times when the windows fog up I turn the AC on.
I have never had a problem with "moisture in the system that is turning moldy". In fact the opposite: when the temps are below 65 heat is on: if there were any moisture the heat will quickly dry it out.
Others may disagree, but when I run the AC my gas mileage does down 2/3 mpg. This is another reason I do not use the AC in the cool/winter months.
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From: Tennessee
W214 E450
99.9% of the time I have my climate control set on "auto". In the summer I set the temperature for 72; in the winter I set the temp for 68.
Having said that, when the temps are below 70 degrees I turn the AC off. Basically from October through the end of April my AC is off: exception when it rains or other times when the windows fog up I turn the AC on.
I have never had a problem with "moisture in the system that is turning moldy". In fact the opposite: when the temps are below 65 heat is on: if there were any moisture the heat will quickly dry it out.
Others may disagree, but when I run the AC my gas mileage does down 2/3 mpg. This is another reason I do not use the AC in the cool/winter months.
Having said that, when the temps are below 70 degrees I turn the AC off. Basically from October through the end of April my AC is off: exception when it rains or other times when the windows fog up I turn the AC on.
I have never had a problem with "moisture in the system that is turning moldy". In fact the opposite: when the temps are below 65 heat is on: if there were any moisture the heat will quickly dry it out.
Others may disagree, but when I run the AC my gas mileage does down 2/3 mpg. This is another reason I do not use the AC in the cool/winter months.
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2022 GLE 350 & 2024 E 450
I always have my car on auto with ac on. The car was in the dealership for about a week for something non-related. Not sure if they did something with the auto/ac while it was there. Once I got the car back, I noticed the smell when air was blowing and engine was off, which means ac was off.
I drove the car today today with auto/ac both on. There was a faint vinegar smell in the beginning but went away quickly. The other much more foul smell never came back after I ran the air on high yesterday.
I drove the car today today with auto/ac both on. There was a faint vinegar smell in the beginning but went away quickly. The other much more foul smell never came back after I ran the air on high yesterday.
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What was the reason why in the past (not sure if still the case) MBs in the USA don't have residual heating mode. A/C (Rest) ? Basically when you are done driving and turn off the ignition, you press the A/C button that also says Rest and the vehicle will circulate air for 20 or 30 minutes. Forgot if it was 20 or 30 to dry things out, that was true before mild-hybrid existed.
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Sorry to see this feature has been deleted.
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From: The Middle of the Fairway
2025 E450 All Terrain Wagon, Nautical Blue Metallic, Macchiato Beige/Black Interior
I had it in my 2014 W212 E350 Wagon. I believe I had it in my W213 2017 E300 Sedan. I believe I also had it in my 2001 C320 Wagon. I did not have it in my W213 2018 E400 and my W214 E450 does not have it, though it is referenced in the owners manual.
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