A/C odor after driving for 1+ hrs
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GL550
A/C odor after driving for 1+ hrs
I have a different sort of AC odor that has been bothering me for the last year or so on my 2013 GL550. It only occurs when the AC is on and after driving for at least an hour, although it is not 100% reproducible. It also seems to occur much more easily in hot weather ( 80 +).
The smell is kind of a weird faintish chemical smell, not a musty wet dog smell. I find that I have difficulty breathing when this happens and I have to turn off the AC right away. The smell clears after about a minute or less.
If I turn on the AC again usually the smell comes back reasonably quickly. However it can take some time for it to happen the first time. If it isn't hot out then it might not produce the smell at all, with say 1.5 hrs of driving. With the AC off the problem never happens.
I have had the car inspected carefully for leaks in the AC system by the dealer, even with dye in the system, but no leaks are obvious. They did replace the cabin air filter and disinfect the system as if it was a mold/mildew problem, but that has had no impact on the problem.
My first assumption was that perhaps the Freon was leaking intermittently. I guess most Freon leaks are not intermittent. Anyway, there is no obvious loss of coolant in the AC system, and no obvious leaks in the plumbing that can be seen easily. They haven't taken the dash apart to check in there because they can't repro the problem - because it takes warm weather and quite a bit of driving. Living in the NW the weather here does not require AC that often.
Has anyone else had an issue like this where the smell comes on after an hour or two of driving and smells chemically?
thanks
Jim
The smell is kind of a weird faintish chemical smell, not a musty wet dog smell. I find that I have difficulty breathing when this happens and I have to turn off the AC right away. The smell clears after about a minute or less.
If I turn on the AC again usually the smell comes back reasonably quickly. However it can take some time for it to happen the first time. If it isn't hot out then it might not produce the smell at all, with say 1.5 hrs of driving. With the AC off the problem never happens.
I have had the car inspected carefully for leaks in the AC system by the dealer, even with dye in the system, but no leaks are obvious. They did replace the cabin air filter and disinfect the system as if it was a mold/mildew problem, but that has had no impact on the problem.
My first assumption was that perhaps the Freon was leaking intermittently. I guess most Freon leaks are not intermittent. Anyway, there is no obvious loss of coolant in the AC system, and no obvious leaks in the plumbing that can be seen easily. They haven't taken the dash apart to check in there because they can't repro the problem - because it takes warm weather and quite a bit of driving. Living in the NW the weather here does not require AC that often.
Has anyone else had an issue like this where the smell comes on after an hour or two of driving and smells chemically?
thanks
Jim
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2015 Ram 2500, former 2013 GL350, 2007 GL450
This is a fairly common issue, a search in the X166 forum wil find it, I seem to remember it's some issue with water accumulating and getting stale.
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I have had customers who (or their spouse) set the temp setiing to min - and if left in that position the evaporator coil inside the system will freeze - and as it feezes up can cause a slightly acrid smell - and then that compounds when the engine is turned off and the frost melts - leading to water accumulation in the system.
Now - interestingly - when I question a customer if they are leaving the temp at min - they invariably say "no" - and when they bring their rig into service, yes it is set on min..
I am not saying this is your specific problem - I am just relating that this is what I have encountered in other select instances
Now - interestingly - when I question a customer if they are leaving the temp at min - they invariably say "no" - and when they bring their rig into service, yes it is set on min..
I am not saying this is your specific problem - I am just relating that this is what I have encountered in other select instances
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GL550
I don't think my problem is the normal water accumulation in the evaporator and subsequent mold production when the car is left hot and wet for a while. My problem only occurs when driving the car for several hours. It isn't a "turn on the car and it smells" problem.
However you do mention that sometimes there is an acrid smell right as the evaporator freezes up, and that could be related to my problem since mine is definitely an "in use" smell. I have had it occur in the Palm Springs area, where I wouldn't expect there to be a lot of humidity to freeze up the condenser, by I don't really know.
Do you have any more info on that slightly acrid smell when the evaporator freezes up?
Jim
However you do mention that sometimes there is an acrid smell right as the evaporator freezes up, and that could be related to my problem since mine is definitely an "in use" smell. I have had it occur in the Palm Springs area, where I wouldn't expect there to be a lot of humidity to freeze up the condenser, by I don't really know.
Do you have any more info on that slightly acrid smell when the evaporator freezes up?
Jim
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A gaggle of MB's
The acrid smell from a "freezing" evaporator is similar to the smell from a frosted up freezer - in the select cases I mentioned where the owner/spouse keep the temp setting either on min, or too cold - under 66/64 - for too long thinking it helps the cabin get colder/faster - and evap starts to frost up - which in turn lowers cooling efficiency - never giving the aircon a chance to do it's proper job..
That's the situation that has come up on 2/3 occasions on front air.
That's the situation that has come up on 2/3 occasions on front air.
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GL550
I am curious why freezing the evaporator would cause an odor and I'm wondering if maybe that is what is happening to me, but I definitely didn't have the thermostat turned way down - more like 72-74. Although having it turned low may not be the only way to freeze the evaporator. So why would there be an odor when the evaporator freezes? I could certainly categorize the odor I smell as acrid.
I just bled a few tiny puffs of Freon from the AC on my GL550 to test smell the Freon and it doesn't smell much. The smell I get inside the vehicle seems stronger and sharper although both leave me feeling a bit weird and slightly dizzy. Can't really tell if they are the same or not.
Is there something going on with the freezing action where the ice expands as it freezes maybe putting pressure on the coils and causing a temporary leak in the evaporator, or maybe there is some pressure relief valve going off or something?
Any thoughts on what causes the smell?
I just bled a few tiny puffs of Freon from the AC on my GL550 to test smell the Freon and it doesn't smell much. The smell I get inside the vehicle seems stronger and sharper although both leave me feeling a bit weird and slightly dizzy. Can't really tell if they are the same or not.
Is there something going on with the freezing action where the ice expands as it freezes maybe putting pressure on the coils and causing a temporary leak in the evaporator, or maybe there is some pressure relief valve going off or something?
Any thoughts on what causes the smell?
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09 GL 320
I am curious why freezing the evaporator would cause an odor and I'm wondering if maybe that is what is happening to me, but I definitely didn't have the thermostat turned way down - more like 72-74. Although having it turned low may not be the only way to freeze the evaporator. So why would there be an odor when the evaporator freezes? I could certainly categorize the odor I smell as acrid.
I just bled a few tiny puffs of Freon from the AC on my GL550 to test smell the Freon and it doesn't smell much. The smell I get inside the vehicle seems stronger and sharper although both leave me feeling a bit weird and slightly dizzy. Can't really tell if they are the same or not.
Is there something going on with the freezing action where the ice expands as it freezes maybe putting pressure on the coils and causing a temporary leak in the evaporator, or maybe there is some pressure relief valve going off or something?
Any thoughts on what causes the smell?
I just bled a few tiny puffs of Freon from the AC on my GL550 to test smell the Freon and it doesn't smell much. The smell I get inside the vehicle seems stronger and sharper although both leave me feeling a bit weird and slightly dizzy. Can't really tell if they are the same or not.
Is there something going on with the freezing action where the ice expands as it freezes maybe putting pressure on the coils and causing a temporary leak in the evaporator, or maybe there is some pressure relief valve going off or something?
Any thoughts on what causes the smell?
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'01 S500 AMG Sport, ABC,Distronic,Rear Side Shades // '10 E350 P2, Pano, BLK/ALM,4MATIC Sport
I have a different sort of AC odor that has been bothering me for the last year or so on my 2013 GL550. It only occurs when the AC is on and after driving for at least an hour, although it is not 100% reproducible. It also seems to occur much more easily in hot weather ( 80 +). The smell is kind of a weird faintish chemical smell, not a musty wet dog smell. I find that I have difficulty breathing when this happens and I have to turn off the AC right away. The smell clears after about a minute or less. If I turn on the AC again usually the smell comes back reasonably quickly. However it can take some time for it to happen the first time. If it isn't hot out then it might not produce the smell at all, with say 1.5 hrs of driving. With the AC off the problem never happens. I have had the car inspected carefully for leaks in the AC system by the dealer, even with dye in the system, but no leaks are obvious. They did replace the cabin air filter and disinfect the system as if it was a mold/mildew problem, but that has had no impact on the problem. My first assumption was that perhaps the Freon was leaking intermittently. I guess most Freon leaks are not intermittent. Anyway, there is no obvious loss of coolant in the AC system, and no obvious leaks in the plumbing that can be seen easily. They haven't taken the dash apart to check in there because they can't repro the problem - because it takes warm weather and quite a bit of driving. Living in the NW the weather here does not require AC that often. Has anyone else had an issue like this where the smell comes on after an hour or two of driving and smells chemically? thanks Jim
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GL550
The dealer has been all over the car 4 or 5 times in the last year and a half and can't find anything wrong. They did fix a couple of coolant leaks and tried to tell me that might have been the problem, but coolant leaks didn't fit with the fact that the AC had to be on to run into the problem. Anyway, the problem still happens even after fixing the coolant leaks.
Something is definitely causing an odor but no one knows what it is. Best guess so far is the acrid smell that fabbrisd1 mentioned when the evaporator freezes up, but my dealer certainly hasn't heard of that. I don't think Mercedes customer support has heard of that either. I don't understand why there would be such an odor when the evaporator freeze up either, but it at least fits with circumstances required to have the problem. I have never smelled this sort of thing on any other car - I would like to get it fixed. Luckily I don't us the AC much, but when I do I'd rather not have this smell.
Something is definitely causing an odor but no one knows what it is. Best guess so far is the acrid smell that fabbrisd1 mentioned when the evaporator freezes up, but my dealer certainly hasn't heard of that. I don't think Mercedes customer support has heard of that either. I don't understand why there would be such an odor when the evaporator freeze up either, but it at least fits with circumstances required to have the problem. I have never smelled this sort of thing on any other car - I would like to get it fixed. Luckily I don't us the AC much, but when I do I'd rather not have this smell.
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GL550
The problem seems to have been fixed on the 4th or 5th attempt by the dealer. I have driven the car extensively in the heat the last two months and I don't detect any odors. The last time I had the vehicle in for the problem the dealer ran though a set of procedures with a Topic number of LI83.30-P-059119. It seems that this procedure must have solved the problem.
Under "Cause" in the procedure it says "Oxidization products of the cavity preservation can enter the interior compartment via the air conditioning". The procedure involves taping over various bodyshell holes and cleaning the evaporator of the A/C unit. It says use only 2 litres of warm tap water, and don't use ContaSept disinfectant!
Maybe this info is useful to someone else...
Under "Cause" in the procedure it says "Oxidization products of the cavity preservation can enter the interior compartment via the air conditioning". The procedure involves taping over various bodyshell holes and cleaning the evaporator of the A/C unit. It says use only 2 litres of warm tap water, and don't use ContaSept disinfectant!
Maybe this info is useful to someone else...
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I'll try to post a pdf of the doc a bit later if I can.
Just to update my experience a bit further, I had thought the problem was fixed but it wasn't completely fixed. Driving in 100 deg F heat for 8 hrs, and the problem came back very strongly - I had to turn off the ventilation completely. The dealer had another go at fixing it, and apparently they learned from Mercedes that the undercoating material on the 2013 GL550 did not set properly. That undercoating combined with heat and water from the AC unit creates the noxious odor. The only way to fix it is to block all of the holes in the ventilation system and maybe the body in general that can allow air from undercoated areas of the body to reach into the cabin area.
Their latest fix to the problem involved essentially what they had done the previous time, which was to close off some holes between the body/ventilation system and the cabin. Maybe they got updated info from Mercedes about additional areas that needed to be closed off in addition to what they closed off the previous time - not sure. But this was the first time that Mercedes actually acknowledged their was a problem and they knew how to fix it. Your mileage may vary on this though since when I talked to an actual Mercedes rep, he said he wasn't aware of any issues that could cause the problem....
Jim
Just to update my experience a bit further, I had thought the problem was fixed but it wasn't completely fixed. Driving in 100 deg F heat for 8 hrs, and the problem came back very strongly - I had to turn off the ventilation completely. The dealer had another go at fixing it, and apparently they learned from Mercedes that the undercoating material on the 2013 GL550 did not set properly. That undercoating combined with heat and water from the AC unit creates the noxious odor. The only way to fix it is to block all of the holes in the ventilation system and maybe the body in general that can allow air from undercoated areas of the body to reach into the cabin area.
Their latest fix to the problem involved essentially what they had done the previous time, which was to close off some holes between the body/ventilation system and the cabin. Maybe they got updated info from Mercedes about additional areas that needed to be closed off in addition to what they closed off the previous time - not sure. But this was the first time that Mercedes actually acknowledged their was a problem and they knew how to fix it. Your mileage may vary on this though since when I talked to an actual Mercedes rep, he said he wasn't aware of any issues that could cause the problem....
Jim
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gl550
I have a similar problem on a 2014 GL550.
Where is the undercoating located?
I get headaches, dizziness, sore throat from the chemical odor when engine is hot.
Most dealerships are unaware of these issues and just say nothing is wrong. How do I address problem with dealerships?
thanks!
Where is the undercoating located?
I get headaches, dizziness, sore throat from the chemical odor when engine is hot.
Most dealerships are unaware of these issues and just say nothing is wrong. How do I address problem with dealerships?
thanks!
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honda
You can discuss with the dealer about LI83.30-P-059119 whether it's applicable to your vehicle.
In my case, I have a 2013 GL 450 and had experienced the AC bad odor for several thousand miles. I don't know if the above fix was ever applied to my GL and I don't seem to get the smell anymore. One of the service agents recommended that the AC settings should be always set to auto... you do not manually change the temperature setting. Even if you change to a lower or higher temperature ...always click on auto. I keep the temperature to around 70 - 72 degree and use auto. It seems to have done the trick...but keeping my fingers crossed!
In my case, I have a 2013 GL 450 and had experienced the AC bad odor for several thousand miles. I don't know if the above fix was ever applied to my GL and I don't seem to get the smell anymore. One of the service agents recommended that the AC settings should be always set to auto... you do not manually change the temperature setting. Even if you change to a lower or higher temperature ...always click on auto. I keep the temperature to around 70 - 72 degree and use auto. It seems to have done the trick...but keeping my fingers crossed!
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The problem I'm having is not AC bad odor. In fact I still get sick without the vents or AC on. It seems that there is a body plug or undercoating or holes in the ventilation system or inside dash that is letting in chemical fumes or perhaps engine smells from around the wheel wells. The odor is very faint almost unnoticeable something like perfume or candle wax. It is a very slight chemical odor only when the engine is hot and vehicle moving. It seems that the air pushes chemical smell inside cabin. After driving vehicle I feel I have been smoking with sore throat and lung irritation along with bad headaches.
Thanks for the advice.
Thanks for the advice.
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gl550
What is the ac odor?
Most smells coming from vents are from bacteria, mold, mildew and actually non-toxic. They might stink momentarily but they don't get you sick. That is a myth that industry propogates.
VOC offgassing and engine fumes are the real toxic chemicals.
The cabin filter does nothing but prevent dust and dirt from entering cabin. These organic materials don't get people sick.
Most smells coming from vents are from bacteria, mold, mildew and actually non-toxic. They might stink momentarily but they don't get you sick. That is a myth that industry propogates.
VOC offgassing and engine fumes are the real toxic chemicals.
The cabin filter does nothing but prevent dust and dirt from entering cabin. These organic materials don't get people sick.
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GLS450
Mercedes GLS450 AC Smell
I have a different sort of AC odor that has been bothering me for the last year or so on my 2013 GL550. It only occurs when the AC is on and after driving for at least an hour, although it is not 100% reproducible. It also seems to occur much more easily in hot weather ( 80 +).
The smell is kind of a weird faintish chemical smell, not a musty wet dog smell. I find that I have difficulty breathing when this happens and I have to turn off the AC right away. The smell clears after about a minute or less.
If I turn on the AC again usually the smell comes back reasonably quickly. However it can take some time for it to happen the first time. If it isn't hot out then it might not produce the smell at all, with say 1.5 hrs of driving. With the AC off the problem never happens.
I have had the car inspected carefully for leaks in the AC system by the dealer, even with dye in the system, but no leaks are obvious. They did replace the cabin air filter and disinfect the system as if it was a mold/mildew problem, but that has had no impact on the problem.
My first assumption was that perhaps the Freon was leaking intermittently. I guess most Freon leaks are not intermittent. Anyway, there is no obvious loss of coolant in the AC system, and no obvious leaks in the plumbing that can be seen easily. They haven't taken the dash apart to check in there because they can't repro the problem - because it takes warm weather and quite a bit of driving. Living in the NW the weather here does not require AC that often.
Has anyone else had an issue like this where the smell comes on after an hour or two of driving and smells chemically?
thanks
Jim
The smell is kind of a weird faintish chemical smell, not a musty wet dog smell. I find that I have difficulty breathing when this happens and I have to turn off the AC right away. The smell clears after about a minute or less.
If I turn on the AC again usually the smell comes back reasonably quickly. However it can take some time for it to happen the first time. If it isn't hot out then it might not produce the smell at all, with say 1.5 hrs of driving. With the AC off the problem never happens.
I have had the car inspected carefully for leaks in the AC system by the dealer, even with dye in the system, but no leaks are obvious. They did replace the cabin air filter and disinfect the system as if it was a mold/mildew problem, but that has had no impact on the problem.
My first assumption was that perhaps the Freon was leaking intermittently. I guess most Freon leaks are not intermittent. Anyway, there is no obvious loss of coolant in the AC system, and no obvious leaks in the plumbing that can be seen easily. They haven't taken the dash apart to check in there because they can't repro the problem - because it takes warm weather and quite a bit of driving. Living in the NW the weather here does not require AC that often.
Has anyone else had an issue like this where the smell comes on after an hour or two of driving and smells chemically?
thanks
Jim
