Outside air vs recirculating inside air

[nomech]

I've noticed that when I have the button to recirculate the air inside the cabin, I can still smell the outside air. I'll add that the defrost isn't on because I know that will cause outside air to enter the vehicle. I bought my 2020 Tahoe brand new, but I suppose that doesn't mean it didn't have an issue with the vent/whatever controls inside vs outside air (possible a damper?).

Has anyone else experienced this or is this something specific to my vehicle?

Thanks.

 

[Joseph Garcia]

I believe that even with the HVAC system set to Recirculate, there is still up to 15% fresh air entering the flow as a safety feature to prevent potential carbon monoxide poisoning, in the event of an exhaust leak.

 

[nomech]

I believe that even with the HVAC system set to Recirculate, there is still up to 15% fresh air entering the flow as a safety feature to prevent potential carbon monoxide poisoning, in the event of an exhaust leak.

That makes sense I've actually read an article stating that if you 'feel tired' while driving, open up the windows and get fresh air in there. That being said, I really wish 15% wasn't being introduced into the cabin because there are times when I'm in traffic and stuck behind a truck with a bad diesel smell, I can't do anything to get it out of the cabin. That's why I thought something was wrong because I looked down and recirc was already 'on' and I could still smell the diesel. Other cars I've been in (all foreign, ironically) I have always been able to click recirc and I never smell outside air.

 

[swathdiver]

I've noticed that when I have the button to recirculate the air inside the cabin, I can still smell the outside air. I'll add that the defrost isn't on because I know that will cause outside air to enter the vehicle. I bought my 2020 Tahoe brand new, but I suppose that doesn't mean it didn't have an issue with the vent/whatever controls inside vs outside air (possible a damper?).

Has anyone else experienced this or is this something specific to my vehicle?

Thanks.

How old is your cabin filter?

 

[nomech]

How old is your cabin filter?

Not old at all, I change it along with the engine air filter regularly. Both were changed last month.

 

[swathdiver]

There can sometimes be an issue where the recirculate or fresh air door doesn't close completely or as the vehicles age, the foam shrinks or falls away and doesn't seal properly anymore letting in outside air.

I'm currently having an issue where my mode door is bleeding in too much outside air when in recirculate mode making the cabin very noisy. System is quiet with fresh air, but smelly from all those poorly maintained vehicles out there!

 

[Doubeleive]

I've noticed that when I have the button to recirculate the air inside the cabin, I can still smell the outside air. I'll add that the defrost isn't on because I know that will cause outside air to enter the vehicle. I bought my 2020 Tahoe brand new, but I suppose that doesn't mean it didn't have an issue with the vent/whatever controls inside vs outside air (possible a damper?).

Has anyone else experienced this or is this something specific to my vehicle?

Thanks.

the only vehicle I know of that will prevent most of the outside air from entering is a tesla.
otherwise air makes it's way in, like it or not. there is nothing you can do about it.
the rear vents in particular are not sealed in any manner whatsoever, they are just slotted to prevent rain from coming inside.
it's also why your ears don't pop from pressure when someone closes a door.

 

[nomech]

the only vehicle I know of that will prevent most of the outside air from entering is a tesla.
otherwise air makes it's way in, like it or not. there is nothing you can do about it.
the rear vents in particular are not sealed in any manner whatsoever, they are just slotted to prevent rain from coming inside.
it's also why your ears don't pop from pressure when someone closes a door.

Thanks for that info. I wish they were like foreign cars. Zero outside smell issues with those vehicles.

 

[Doubeleive]

Thanks for that info. I wish they were like foreign cars. Zero outside smell issues with those vehicles.

all cars will get air inside, otherwise you would hear about dead people sleeping inside, etc, etc
and it's also why many state have guidelines/rules/laws that dictate how long a vehicle can (or should) idle on remote start because idiots park them in the garage and leave it running, which HAS resulted in dead people

 

[mountie]

I've never noticed a difference......

 

[mountie]

all cars will get air inside, otherwise you would hear about dead people sleeping inside, etc, etc
and it's also why federal guidelines dictate how long a vehicle can idle on remote start because idiots park them in the garage and leave it running, which HAS resulted in dead people

 

[Doubeleive]

I corrected that, no federal law but many state laws.... gm made it 10 minutes to cover there behind...

 

[nomech]

all cars will get air inside, otherwise you would hear about dead people sleeping inside, etc, etc
and it's also why many state have guidelines/rules/laws that dictate how long a vehicle can (or should) idle on remote start because idiots park them in the garage and leave it running, which HAS resulted in dead people

Understood, I guess what I'm saying is that I don't have this issue with foreign vehicles but I do with mine. Maybe there is something wrong with mine, but I also didn't notice this recently, I noticed it when it was still under warranty but it was never a big enough issue to take the car in and try to explain the problem.

 

[mountie]

A '70's VW Bug...... Closing the door will almost blow your ears up !!

 

[Doubeleive]

and...who was it? hyundia? that patented the fart extractor, to vent a drivers seat fart to the back seat

 

[Doubeleive]

Understood, I guess what I'm saying is that I don't have this issue with foreign vehicles but I do with mine. Maybe there is something wrong with mine, but I also didn't notice this recently, I noticed it when it was still under warranty but it was never a big enough issue to take the car in and try to explain the problem.

you could have it checked but it's likely going to have to come out of pocket because the only way to tell for sure if the vent is closed is a visual and manual inspection. a scanner can say it is closed but that really doesn't mean much with these cheap actuators, and even with a manual inspection the foam inside could be deformed or something letting air thru.

 

[nomech]

you could have it checked but it's likely going to have to come out of pocket because the only way to tell for sure if the vent is closed is a visual and manual inspection. a scanner can say it is closed but that really doesn't mean much with these cheap actuators, and even with a manual inspection the foam inside could be deformed or something letting air thru.

I meant, when it was under warranty I could have had it looked at, at no cost. At this point, I'm not taking it to them. If there was something I could look at on my own I'd have to decide if it would be worth it to take the dash apart. It isn't that much of an inconvenience. I mainly wanted to know if I was alone or if this was common.

Thanks.

 

[Doubeleive]

I meant, when it was under warranty I could have had it looked at, at no cost. At this point, I'm not taking it to them. If there was something I could look at on my own I'd have to decide if it would be worth it to take the dash apart. It isn't that much of an inconvenience. I mainly wanted to know if I was alone or if this was common.

Thanks.

in general the actuators will not give you any outward appearance of a problem, sometimes if one is bad it may make a "clicking" noise or you may hear it trying to move multiple times under the dash, but if you have a decent scanner capable of reading body codes then you could see if one or more actuators are having a problem such as a "feedback" error which means it was unable to either go to the position commanded or is unable to read the position, sometimes they will do this random and then be fine 99% of the time, but it will show a "count". that's really the only way you could check it yourself. that and feeling for air blowing from a vent when it shouldn't or feeling cold when it should be warm, etc