Heater issues

[AK Kilted Guy]

I've gone through and searched but am not really finding anything useful.

I have a 96 with the 3.4l engine. I am not getting any heat up front. The fan blows but no real heat.

What I have done so far.

Checked coolant level (ok)

Replaced thermostat

Flushed heater core, finding it is not plugged.

I have also checked the cable that runs underneath the passenger side, and it is moving when the lever is moved.


So what am I missing? Any other suggestions on how to diagnose and fix this?

Oh, it is -22 here right now and the rear heater just isn't cutting it anymore.


Thanks folks!

 

[TheDurk]

Automatic digital or manual control system?

 

[marcel]

Ive got the exact same problem. took it to my mechanic and he said its the heater valve.
sounds like the same thing for you. They are pretty cheap on the internet i just havent got to doing mine yet and not sure how easy it is to DIY

 

[AK Kilted Guy]

Ok, after talking with another local 4Runner guy who had a similar issue, I got it resolved.

He said there is a flap inside the heater unit that was staying open bypassing the heat. He said the lever was underneath the passenger side dash.

So I went outside and started playing with the controls on the dash (manual). At first it seemed like everything was working ok, but after lighting it up good down there and looking closer, I saw a lever and rod that weren't moving no matter what I did with the controls. I pushed that little lever back, and what do you know... heat. Just like that. Turns out that a pivot that it was connected to broke, and it was just hanging free.

About a foot of bailing wire and I got that thing set to blow heat now.

Now, I wonder if I will ever really fix it.......

 

[marcel]

im amazed. that just worked!!!!!

 

[AK Kilted Guy]

im amazed. that just worked!!!!!

That work for you too?

 

[marcel]

yeah! i was going to pay someone 180 bucks to do it but not anymore haha

 

[AK Kilted Guy]

Well, if there's two of us, then there's more. I will take a pic or two tomorrow and add them to this thread.

 

[Mwl4runner]

Thank you AK Kilted Guy! I was about to take my 2000 to the mechanic tomorrow but now I can save some dough and get some bailing wire.

 

[RiverQueen]

94 4Runner with the same problem

I have a 94 with the same problem. Did you figure it out? I have rear heat also, and that works great..it is just the front. Uggggg anything aould be helpful..thanks

I've gone through and searched but am not really finding anything useful.

I have a 96 with the 3.4l engine. I am not getting any heat up front. The fan blows but no real heat.

What I have done so far.

Checked coolant level (ok)

Replaced thermostat

Flushed heater core, finding it is not plugged.

I have also checked the cable that runs underneath the passenger side, and it is moving when the lever is moved.


So what am I missing? Any other suggestions on how to diagnose and fix this?

Oh, it is -22 here right now and the rear heater just isn't cutting it anymore.


Thanks folks!

 

[davejdoyle]

I had the exact same problems as everyone else. Replace the thermostat etc etc, then found this thread. The wire thats connected to the heat knob, that goes under the passenger side dash, had simply fallen out of its holding bracket. I wedged it back into place, which allowed the semi-complicated-looking white plastic linkage thing to operate normally...and instant heat. literally took less than 2 minutes to locate and fix it.

 

[pdx650]

slightly different...I think.

I have the 2.7 liter and the heat control lever in my base '97 4wd is still connected to the valve on the other side of the firewall (where the coolant is diverted from the engine into the heater core inside the cabin area).

This problem started today. The heat is turned all the way up and there is lukewarm air coming through my vents.

I do not know the if the 'flapper' valve on the 3.4 is the same as the 2.7. I've never seen a 3.4 liter v6 internals very much.

help?

 

[yotathang]

I will start off by saying thanks for posting this. I was having the same issue with my 99 limited , I read this and went out to the truck and it was the same exact thing going on with mine. I noticed that when I moved the valve I only get hot air coming out of the two center vents. Did you have the same issue? I also noticed that when I set the temp over 75 I hear a ticking noise coming from the little black box that wires plug into. My controls as far as ac /defrost/auto don't seem to work at all times. Any idea on this issue?

 

[pdx650]

It is sub-freezing temperatures in central Montana and that doesn't help with heating the interior of my 2nd year 3rd gen 'runner. I think I will either have to replace my heater core and/or the radiator to maintain a good passenger compartment heat during colder months.

 

[TXRick]

Thread resurrection!

2001 Limited Manual A/C controls

New radiator, plus I've changed the thermostat, flushed the system, flushed the heater core, burped her, checked the mixer valve (it works but could it be clogged?)...I haven't been able to find this cable you guys are talking about but I would love to check it out. Where exactly is it? All I see when I get under the passenger side are a bunch of black boxes...I even took out the glove box to see better...

Ok, after talking with another local 4Runner guy who had a similar issue, I got it resolved.

He said there is a flap inside the heater unit that was staying open bypassing the heat. He said the lever was underneath the passenger side dash.

So I went outside and started playing with the controls on the dash (manual). At first it seemed like everything was working ok, but after lighting it up good down there and looking closer, I saw a lever and rod that weren't moving no matter what I did with the controls. I pushed that little lever back, and what do you know... heat. Just like that. Turns out that a pivot that it was connected to broke, and it was just hanging free.

About a foot of bailing wire and I got that thing set to blow heat now.

Now, I wonder if I will ever really fix it.......

 

[thinkagain13]

Need help with AC/Heater!

I've been having similar issues ... heat was working great through half of last year, then all of a sudden stopped working. Fluids have been kept up, belts have been replaced, etc etc.

However, just to add a couple more things to the mix ... Our AC only worked briefly after we bought the 4runner ('96, 4x, limited edition, 6-cyl) in 2011. A few months after we bought it, everytime we turned the AC on, it started making a flap sound (like the doors protecting the filters at a pool), and only blew warm air. We figured that will take a lot of money to fix, and have kind of dealt with never using the AC.

Now, the heater isn't working, and, not sure if this is connected or not, when we come to a full stop, then accelerate, there's a trickling sound ... almost sounds more like dead leaves blowing across the street (poetic I know) rather than just a straight drip of water ... This only started happening a couple weeks ago, but it's been over a year since the heater stopped working ...

Any ideas/suggestions?

 

[tyr0981]

OUTSTANDING! i've been racking my brain for weeks over what this could be! you're awesome! THANK YOU!!! this is the cable that moves the valve and had fallen off of the black clip that holds it place:

 

[Family4runner]

So I have a 99 limited I'm unsure if of the pic above is pre 99 I have the digital controls. Anyhow same heater blowing cold. When I turn left knob to turn down temp clicking starts. I go under the hood and manually move heater control valve and clicking stops. Turn the temp up blows cold. But after manually moving heater control valve intense heat instantly. So I'm guessing it's the heater control valve. What y'all think . I dont see any loose wires under pass dash.... Thanks cold in stockton ca

 

[alumarine]

So I have a 99 limited I'm unsure if of the pic above is pre 99 I have the digital controls. Anyhow same heater blowing cold. When I turn left knob to turn down temp clicking starts. I go under the hood and manually move heater control valve and clicking stops. Turn the temp up blows cold. But after manually moving heater control valve intense heat instantly. So I'm guessing it's the heater control valve. What y'all think . I dont see any loose wires under pass dash.... Thanks cold in stockton ca

Sounds like the valve is working.
Seems like it might be what controls the valve.

 

[moparker]

99 4runner heat issue

I have replaced the thermostat, heater control valve and now the heater core. I get heat with the RPM's up. Cool at idle. tried to burp it, nothing. All the doors seem to be working as they should. I am pretty frustrated. The only thing left is the water pump. Any help would be appreciated.