Interior Air Flow (1 Viewer)

[Crain]

All,

Hard to explain but here goes. I noticed that when my climate control system is turned off there is still residual air (hot or cold depending on what the temp dial is set at) that is coming from the front vents. This occurs when the fan is set to off, happens on both the recirculation and fresh air settings and each of the vent adjustment settings (meaning: auto, feet, defrost etc.) Not a huge amount of air coming out.

Not sure that makes sense, but is this normal?

Thank you in advance for your assistance.

Note: My rig does have rear air and ac. Does the rear control unit need to be set to off as well, in order to eliminate the residual air coming out of the front vents?

 

[GotCone?]

My 80 did this worse than my 100.

It is normal best I know.

 

[Trunk Monkey]

If you're just sitting, there shouldn't be any air coming out, but at speed there will be some bleed.

 

[2000UZJ]

No matter what my settings are I always have a little air coming through the far driver side vent when moving. Doesn't bother me, but I did wonder about it.

 

[NMuzj100]

Every car I've ever had did this to some extent. The 100 less than most.

 

[96r50]

I think all newer vehicles are designed to do this as it prevents the exhaust fumes (CO especially) from building up to a potentially toxic or fatal level while driving.

 

[petrotk40]

Mine does this as well. However, at highway speeds it's about the same as the fan on the 2nd highest setting... is that normal? I tried recycled air and it seemed to not blow as hard.

 

[petrotk40]

Note: My rig does have rear air and ac. Does the rear control unit need to be set to off as well, in order to eliminate the residual air coming out of the front vents?

hmm, I'll have to check that out.

 

[OregonLC]

Just a function of high pressure at the inlet (base of windshield) vs low pressure at the vent (sides by tail lights) causing air to flow through the cabin. If you put it on recirc it will stop, although I'd rather have makeup air from outside than continuously re-breath the same air.

 

[lexi4darin]

Yes to all your comments and to petrotk40's comments: Yes the FJ100's are the same as any Toyota product i've driven. If the climate settings are set to "outside air", there will be airflow thru the climate system. The amount of flow depends on the speed the car is moving (slow moving car = less airflowing through the system; fast moving car = more air flow). The temperature of the air is directly related to the outside temperature and the thermostat setting.

Example: It's a cold day outside and you are driving on the Hwy at 65mph. If the climate system is set to outside air and HI heat, there will be a good amount of hot air coming thru the vents of the climate system. To change the position of where you want the air to be blowing, change your settings on the climate control (change to defrost for example). Also, if you slow down, say while merging off the highway to a red light, you'll notice the amount of air flowing from the vents decreases with the speed of the vehicle.

If you want to stop the free flow of air, change the climate system to "recycled air". Any airflow with the system set to recycled air and fan off is just a product of leaks in the system. All of my Toyotas are pretty air tight with the climate system off and the recycled air setting selected.

 

[Dobie]

Funny that this thread popped up. I had just noticed mine does this as well.

 

[scottm]

"Flow through ventilation" was an advertised feature in cars long ago, basically they added outlet vents at the rear of the passenger compartment. I'm not sure when, but I remember seeing ads somewhere, cars have incorporated the feature ever since.

 

[OregonLC]

"Flow through ventilation" was an advertised feature in cars long ago, basically they added outlet vents at the rear of the passenger compartment. I'm not sure when, but I remember seeing ads somewhere, cars have incorporated the feature ever since.

My 63 VW didn't have them and you could feel your ears pop if you slammed the doors!

I think most modern vehicles incorporated flapper style vents behind the tupperware bumpers. Pickups usually have them behind the cab, hidden by the bed. The LX/LX keeps them up high presumably for the ability to forge streams without water coming back in through the vents.

edit: link - Remember When Cars Had Vents? | CarGuyDad