Adjusting water valve to maximize A/C performance (3 Viewers)

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Thanks for the response. I have a '97 4runner with the 3rz-fe 2.7 liter 4 cylinder engine and it is a 4x4. I do have a rear heater which does put out mildly warm air, not warm enough for rear passenger comfort. But I am actually having problems with the main heater for the front controls. The fan works. I have found a replacement valve for the small leaking water valve on the other side of the firewall for 30$. However, I do not know if replacing it will fix the problem. I have to replace it anyway. I think the warmed air is being directed else where, but I don't know how or why. Maybe a flapper door is not operating the way it is supposed to.
I have seen a small (drops forming) leak on the cable connecting the warm/cold lever inside at the hvac controls to the actual valve itself. That is why I have to replace it.
 
I would re-post this in the Mini truck/4Runner forum...as you will get a more definitive response.

Try this...

95+ Gen Toyota Trucks
 
Wife tells me the other day that the a/c wasn't cooling? It is January, but we also live in Texas. One day 20* next day 80*? So I look into it and a skipped and shreaded belt!
Easy enough! For once!!
Oh yeah, I checked the water.mix valve when I bought the truck.

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thanks. All summer I kept thinking, this is not blowing as cold as it used to. Just looked, saw a good 4-5mm gap off the stop, adjusted it, and it blows much cooler now. Very cool, and 5 minute fix.
 
i thought this thread was going to solve my cooling/heating issue... my ac isn't super cold and heater blows cold air... so i check this valve and sure enough, the cable is stuck and doesn't hardly move when i go from full HOT to full COLD. so i tried to take the cable out and readjust it but the cable itself seems like it's bounded up and doesn't push or pull... i took the cable off of the valve and pushed the valve all the way to the "HOT" side and waited for HOT air... but it was still blowing cold air... any help? thanks

I am having this same exact issue. Any ideas? Thanks!
 
I am having this same exact issue. Any ideas? Thanks!

Ok so, I figured out this issue. The problem was the servo motor behind the radio was kinda gummed up. It looked like dirt and goo had gathered over time. All I did was give it a bit of encouragement to move in the right direction, and it did. I them moistened it with PB blaster, and it started to move on its own without any further encouragement.

I don't know how long this will last, but it works for now. :0)
 
Greetings from sunny (and hot) Tampa, FL. Stumbled across this thread right after driving and feeling like my AC was way not cold enough. Will contribute a couple of close-up pics of this phenomenon. I am old and tired and my engine was very hot, so I had to really reach to get these close enough. I cannot quite see how this cable clamp works. Do you just pry it open with a screwdriver and then pull the cable toward the front or am I missing something (look at the second pic).

As you can clearly see, I have the now infamous 4 mm gap.

AC_Cable1.JPG

AC_Cable3.JPG
 
there's a bracket holding the rubber part of the cable. while the temp adjuster is put to max cold, unclamp the bracket it and move the rubber part of the cable up until it reaches the stopper and clamp it back down.
 
This photo is not focused very well, but it looks like I got the lever all the over to the stop. I decided to pull the cable after setting the temp up a little up off the minimum (see second photo). This way if the cable slips again I should be able to notice from inside the car when the slide moves all the way over to the left. Have not checked the temp yet. I plan to clean the evaporator and blower area this weekend. AC_cable6a.jpg
AC_cable7a.jpg
 
You guys freaking rock. I thought that some how the previous owner charged a leaking system just long enough for it to blow cold on the test drive. I got the rig in western wa where you pretty much never need ac and insisted that it must work in order for me to purchase it. So i landed at the airport and dude picked me up and it was blowing cold, i had my buddy test drive it before i got there and he said it was blowing cold. So i get into the hot side of the state kick on the ac and its blowing hot man like strait heat. I was freaking out. 14 hours of driving with the windows down, cost me a set of door speakers. Got home tore the dash back apart to see if i screwd something up putting it back together after putting in satellite radio and it started blowing slightly cooler. So to the forum i went and sure enough. Blows ice cold. Thank you so much brothers, if any of you are ever passing through eastern montana/nd hit me up.
 
The small gap when the valve is fully engaged against the stop may be there to stop the coil from freezing. This minimum flow might stop ice from forming on the evaporator coil in humid weather.
 
This is an old thread that almost all the veterans here on MUD know about, but...

EVERYBODY should check this valve adjustment (unless you never use your AC).
I am embarrassed to admit that I finally fixed this today. It is fast (a few minutes), it does not take any tools, and it is a pretty easy adjustment the first time out (and uber-easy once you know what you are doing). Mine was substantially out of adjustment. Cheers.
 
Last summer, my first with the LC, I just pushed it all the way over and left it there. The other night I needed defog but didn't want the cold air so I tried to get warmish air out of it but was unable to. As soon as I slid the auto AC control near 62* (only about a quarter inch from full cold) it began blowing hot, very hot. There was no in-between, just hot or cold. Is this normal? If not could it be related to this valve adjustment?
 
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Hmmmm, good question. Have you altered yours? If you look @ the valve it's obvious how it operates. To the far DS is coldest & to the far PS is the hottest. When yours is blowing hot air, where is the 'valve' @?
 
Last summer, my first with the LC, I just pushed it all the way over and left it there. The other night I needed defog but didn't want the cold air so I tried to get warmish air out of it but was unable to. As soon as I slid the auto AC control near 62* (only about a quarter inch from full cold) it began blowing hot, very hot. There was no in-between, just hot or cold. Is this normal? If not could it be related to this valve adjustment?
Mine does the same thing. I'm doing this adjust ment tomorrow as I already found it to be about 4 mm off closed. I have also heard that the solder points on the climate control unto could have small cracks and can be resoldered to fix that problem.
 
Mine does the same thing. I'm doing this adjust ment tomorrow as I already found it to be about 4 mm off closed. I have also heard that the solder points on the climate control unto could have small cracks and can be resoldered to fix that problem.
I did this mod today but found that when climate control is on cold all the way left the valve closes properly. But if I move the climate control right half an inch it goes eide open on the valve.. no spot in between all the way open or all the way closed. Will have to pull climate control unit and bench test.
 
for those trying to solve this issue, I wanted to add:

if you have an aftermarket stereo installed, the new bundle of wires may be getting in the way of the cable servo motor movement.

with everything pulled out (stereo, ashtray, ac, hazard etc) I tested it and I found that it worked, where before the cable/valve at the firewall was not moving. I found a plug had gotten in the way of one of the tracks of the motor movement, blocking the cable from being pushed/pulled. cleared everything from around it (stuffed it up actually where there was some room) and it works as it should.

I wonder if I hadn't checked it, that after time something might eventually have broken around the control box.
 

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