Hot air through vents

[chronos45]

Max a/c, fan off, and temperature slider to coldest. I have hot air coming from the vents or cold if its cold outside. I think the little door that lets air from the outside is not closing well enough. No air coming out at idle, but it increases as speed increases. It is very hot where I live (115+ every day no joking) so I need this fixed because my a/c is not cold enough, maybe you could say it is fresh. Instead of getting colder at higher speeds it gets hotter. Any suggestions?

I dont think it is the blender door, or related to the heater core as it has been bypassed.

 

[snoman6115]

vaccum lines. had that when my auto hubs went out got air rushing through even with all controls off.

 

[The_Dealer]

mine does it too, cant figure out what it is, i dont have my a/c hooked up, but its a pita when i go down the road with the windows down and hot air is comming out, o well maybe the duraspark will solve alot of my problems

 

[budro]

remove the glove box there is the vaccum actuator right to the right above the kick panel. There will be a vacuum line that comes from the vacuum tree on the upper intake to above the ac box under the hood through the firewall along the dash and to the vaccuum switch on the hvac control below the radio. Then it runs back to the actuator. Best thing to get is a hand vaccuum pump and test every section. Take a sharpie and draw a line on the actuator arm to make sure it moves up and down.

I fought these for a whole summer look for scuffed lines under the glovebox by the kick panel or the juction points for the hard plastic lines thats where mine were leaking. Also if you feel it open up and get warm air when you are going up a hill then you still have a small leak somewhere. Thats what I fought for a while.

 

[chronos45]

Max ac should prevent outside air from getting in, right? Well, when switched from ac to max ac the door under the glovebox opens which means it works and I dont have a vacumm leak. From where outside the truck does it get that air? Is it from the holes between the wiper arms? I believe the best solution for me is to close that vent from the outside. Maybe I'll do it the right way when winter arrives.

 

[chronos45]

bump

where is it entering from? anybody?