Heater not blowing hot air...

Good morning forum. Need some advice. Turned on my defrost this morning on my 07 Tacoma Double Cab 4X4 and all I got was cold air even after the engine reached normal operating temps. Some have advised that I need to replace a "heater control valve" located under the hood, but for the life of me I can’t locate anything that might look like it. I've checked on the internet and have not found any info, I' hoping that one of you guys/gals can assist. Any assistance or advice that you shed would be greatly appreciated. I’m hoping to fix/correct the situation myself if possible as $$ is tight this week. Albeit I have time since it's still 90 degrees outside here in Alabama . Thanks. Shorty sends...

 

The 2nd gen tacomas do not use a heater control valve, so you were given a bum steer, and thats why you could not find such a valve. Rather than shutting off or regulating the coolant flow through the heater core, your truck has what's know as a "blend air" heater, where there is an an air door inside the heater box to direct the airflow through or around the heater core, while the coolant flow through the core is full and uninterupted.

So, there are two basic possibilities if you aren't getting heat. First, there is an airlock in the cooling system - if you haven't had the coolant drained since the last time the heater worked, and the level is good, its probably not the cause. You can feel that the heater hoses are hot going in and out from the firewall. Blockage is also a possibilty, but hot hoses in and out will confirm the coolant is flowing.

The other possibility is that the electronic actuator for the blend air door has bit the dust, and will need to be replaced.

 

I went out and looked at my '05 to see if the heater valve was on the firewall, like my '02 Tundra. No luck

But I did find two problems with our trucks that have to do with the loss of heat.

One is a gear in the air mix servo:
http://www.toyotanation.com/forum/61-2nd-generation-2005/285024-air-mix-problems-heater.html

The other has to do with insulating foam on the airbox door coming unglued and blocking the air to the heater core.
http://www.toyotanation.com/forum/61-2nd-generation-2005/373134-2007-toy-tacoma-heater-doesnt-blow-hard-anymore.html

Hope it's the first one, the second seems like a bitch taking the whole dash apart

 

Landphil and Agent Smith, thanks for the quick reply.
The hoses coming in and out of the fire wall are both hot to the touch so I don’t know if that negates the blockage theory?
WRT to the "electronic actuator for the blend air door" can you give me lead as to where it is located? Is replacement of said actuator a do it yourself job or are special tools needed? BTW is this actuator the same as the air mix servo issue suggested in Agent Smith thread reference?
There is plenty of air coming out of the vents in both the heater (warm) and ac (very cold) mode so I do not believe that the "falling foam" is the issue.
Agent Smith, I read the post at http://www.toyotanation.com/forum/61...ms-heater.html and it’s all over the map. Quite frankly I left more confused than before I started reading it. I do appreciate you assisatance though.
I was also wondering if perhaps there is a temp sensor behind the switch on the dash that regulates between AC and Heat.
Anyway thanks for your assistance and I'll be standing by for your responses. Luckily it's still in the 90s here in Alabama.
Best. Shorty sends…

 

I had a chipmunk nest in my dash.

Pop your hood, remove the cowl trim at the bottom of the windshield, remove your glovebox, remove air cabin filter, remove nest, vacuum out airbox, growl every time you start truck cause you smell chipmunk shit.

 

Don't think it's a chipmunk nest here...

Still no joy in resolving.

 

Actuator = servo, same thing. There are three in total - one for fresh / recirc, one for mode (floor/dash/defrost) and one for temperature. I can't tell you off the top of my head where the temperature one is located as I haven't had any issues with mine, but I'll take a peek later and see if I can snap a picture. The worst part is usually access, other than that they are pretty simple and easy to replace.

 

Get ahold of a can of Wurth Quickfresh, follow the directions on the can, and the growling will cease.

 

Oh, cool, thanks for the advice, when ever I start my truck, it stinks for 15 seconds, then goes away. Just annoying.

A chipmunk got in my neighbors Camry and chewed their trany wires, laughing! Little buggers

 

Just invite my ex-mother-in-law to ride with you. She blows enough hot air to heat the entire state of Alabama.....

 

landphil, thanks for your time. I'll be standing by. Have a great week. Shorty sends...

 

You're already using your heater? In Alabama?

 

Well sort of... I was out camping and the vehicle obviously spent the night outside. When I went to drive off I turned the defrost on and even after reaching the 180 degree mark on engine temp, nada, zero, zilch hot air coming out of defrost and/or vents... So, yes is the answer to your question. Mind you though during the day it's in the 90s! Fortunately there are no issues with the AC.