Drafty Cab

Well here we go again. "My feet are cold. When you gonna fix this?"

Anybody got ideas?

 

My thought is what already has been stated...
likely something to do with the fresh air intake not sealing fully when closed.
Or just isn't closing fully.

Are you sure the AC isn't still on ?

Maybe stuff a rag down into/ontop of the intake/cowling door
and see if the draft isn't diminished some ?

My other thought is...
this wife needs a husband who's not too lazy to dig in...
look for / find the draft source, then correct the fault. Lol

Sit on the passenger side and feel for where the draft is coming from.
If you can't do that... thar's no hope for ya.

You should list exactly what it is you have tried up to this point
so other reading along have a short list re-cap.

Stuffing a bundle of crap up behind the glove box to block a draft
is not even a good bandaide attempt.

 

just curious and didnt see anyone mention it but where is the switch set to? is it set to blow on the floor? switch it to defrost only and see if thats the problem.

just trying to start with the easiest solution and maybe something overlooked.

 

Boy, you guys are tough!

The air is not on, the controls are where they are supposed to be. Until I can remove the passenger seat and lay on my back to peer up there I think I am going to keep one of these wool blankets in the truck.

I suspect a vent door is not closing tight or something like that. I might drop by the dealer and see if they have encountered this before.

 

hahaha not trying to make you feel like an ass but some of the things people post on forums without checking the obvious. i just like to start with the simple shit first.

 

Any way it could be the grommet in the firewall? As in it's deteriorated or missing this allowing air to pass through and seep down the inside of the firewall to her feet?

Or would the air from the engine bay be warmer than what she's feeling?

 

Tell her to sit in the back seat

 

Unfortunately I don't have one with the sheet of carpet covered plywood I have back there.

So today I removed the seat, glove box, and surrounding bracketry and we went for a ride. The draft seems to be coming from the vent door that isn't sealing as well as it should. Short of disassembling the whole dash how does one get in there to replace that door with foam rubber surface?

 

Update: My local Toyota dealer quoted a price of $650 for the assembly that includes the damper door.

I believe I will be removing the assembly to see if I can re-glue some foam rubber onto the surface. Does anyone have instructions of how to remove the dashboard without detonating the air bag?

 

Well air flows in the cab no matter what, so if you don't have the ac or heater on, but the dial is turned to cold, ambient air will flow into the cab and it will be chilled by the ac system. Try turning it to hot, still without the fan on and warm air should flow into the cab. Unless you don't have ac then disregard this lol.

 

Turn on your recirculate button, even if fan is set to "off". If recirc is off, air always vents into the cab. Maybe I missed you trying this already.

 

The draft she feels is when the air is set to recirculate. This is when the outside air vent is supposed to be turned off. But because the flap door leaks it never completely seals off.

If we have the heat on, with or without the AC:
With recirculate on she feels the cold drafty air blowing at her feet
With recirculate off it seems to build pressure in the cab and limits the amount of draft, but then we get the outside country smells, diesel truck smells and more fogged up windows.

Perhaps next weekend I can rip the dash apart to see if I can get to the unit that contains the flapper door.

 

No sure where the flapper door is, my truck is gutted for a cage I'm building if you know-ish where it is I can try to get some pics for you so you'll know where to go

 

Many thanks for the offer. From inside the cab it is on the upper RH firewall section. Behind and above the level of the glove box. You should be able to see that unique bracket and vertical grill slats as pictured above.

 

That?

 

Looks like a small actuator on the right, the little white arm, maybe that's broken?

 

I unbolted it so you could have a better look.
That's it in the closed position

 

Oh btw, no electrical thus why I unbolted it instead of just turning on recirculate, cause I can't lol

 

My cabin does the opposite.

with recirc off: it has no additional cabin pressure, but allows every external odor to enter.

with recirc on: the cabin's increased internal air pressure becomes more apparent.
but if the mixer/vent door seals properly... external odors generally will not enter.

When the recirc. is on and when the doors are closed.
the cabin pressure must escape thu' cabin air pressure flappers
located rearward of the two front occupants of an ext. cab.
Much like how a flapper valve works for an aquarium air pump.

I'm not sure where these pressure/flapper vents are located on a std cab.

But if those flapper (bladder) vents aren't opening/closing properly.
Then the cabin's air pressure will likely look for another way out.
Thus' causing the mixer/vent door seal to fail... over time.

The flapper vents only allow air flow one way.
Allowing the cabin's internal pressure a place to escape
but if working right... they should not allow anything to enter.

If it leaks air in with the recirc on (air mix/vent door closed)
and you can still smell external odors coming in...
the issue likely has to do with a poor mix/vent door seal.

cheap/temporary fix:
eliminate the draft... by covering the vent opening with duct tape.

In order to reseal /or replace the vent door...
I believe the whole mixer box needs be removed
so that that it can be disassembled.

Or just go to a salvage yard and look for a replacement mixer box.
But be sure it is off a newer 1st gen...
As an older unit might have a bad mixer/vent seal as well.

Like someone suggested prior...

Turn the mix/vent lever to recirc.
Then place the thermostat control knob to heat, without the fan on.
The warm radiator fluid running thru the AC's condenser should reduce the cold draft.
Be sure the AC switch is not on or it could still feed cool air thru.

 

Yes, that is the culprit. My motor and pull rod are working correctly but it seems the foam rubber has dried out and allow air to blow by the closed door. How much effort to disassemble the dash to access it? I would like to disassemble to the point I can apply some new seal to the flapper door.
Many thanks for the info and photos!!