1995 4 Runner No Front Heat

[fd59]

If you figured this out please let us know. But, based on everything you said I would bet that the heater core needs replacing. what is probably happening is that the coolant is flowing down one side of the heater core resulting in your lack of heating. A heater core is basically a small radiator. I have had this happen on my '79 Toyota truck. The radiator had a good flow of coolant making everything look OK, but it would not keep the engine cool. Come to find out, the radiator was flowing the coolant down one side, resulting in the engine wanting to run hot. I replaced the radiator and everything was normal.

I had a similar problem with my Trooper heater core a couple of years ago. It started to blow only luke-warm air, but before I had a chance to replace it, one side blew out and started releasing coolant. After I replaced it you could use the air ducts as a oven.

So, my vote is the core needs replacing.

 

[FISH HUNTER]

Check the return heater hose to see if the water is warm or hot.

 

[jrybon]

'97 no heat

I have the same problem here in Colorado. Last nite I did a thorough inspection: changed the thermostat, back flushed the core, checked the water valve operation, and inspected the hoses for leaks.

Still no luck. The back seat heater (yes, its water-powered from the same supply & return) is cranking, so that helps keep the vehicle usable, and shows that the water system IS working, but it still aint right.

My coworker advised me to look into the air valves that operate inside the dashboard. Apparently they could get stuck open, drawing cold air from outside when that is unwanted. he claims they are vacuum operated.

Has anyone ever messed around with those air mixing valves? Where would the vacuum hoses come through? Do I have to rip the dashboard out to get to it?

 

[jrybon]

'97 NO HEAT

My master-toyota-mechanic-buddy says our Runner uses no vacuum, but DOES have ! 2 ! cables coming off the temperature lever. One goes to the water valve under the hood we have all discussed at great length. The other goes to an air blending damper in the dashboard. He suggested looking up under there and mabye through the glove box to find that mechanism and make sure the end is still attached, and the sleeve is still retained.

I'll post with my findings..

 

[jrybon]

'97 NO HEAT

Check out THIS discussion....
http://www.yotatech.com/f2/heater-help-45058/

 

[fourwd1]

Where exactly is the valve? I think I found the 2 heater hoses, about 1/2" thick with a foam covering? If this is correct, both were indeed very hot.

I assume the valve is probably very close to the hoses, but I'm not sure exactly what I'm looking for. Could someone please clarify for me?

Thanks in advance.

Valve is on the firewall, should ba a cable come thru to operate it.


I had a similar heat question on another Toy BBS where I'm a Tech Advisor yesterday.
Told the guy to make sure the diverter flap in the ductwork moved when the temp control was moved from hot to cold, as it directs the air thru the heater or AC cores depending on setting.
I was right, the cable had come loose from it so it stayed in the cold position.

If both heater hoses going thru the firewall is hot, chances are the above is your problem.

FYI, some are controlled by a vacuum motor instead of a cable, and a vac leak will cause those not to work.

 

[jrybon]

air damper valve

OK Boys. I fixed mine last nite and took pictures. The hot handle has a 2nd push cable that runs under the passenger side of the dashboard to a lever. On mine that cable had been kicked off its retainer and was flexing rather than actuating the lever. It took about 5 minutes to look under the dash while moving the hot handle, identify the loose cable, and push it back into its retainer.

 

[jrybon]

air damper lever

let me see if I can upload this photo...

 

[fourwd1]

Re: air damper valve

OK Boys. I fixed mine last nite and took pictures. The hot handle has a 2nd push cable that runs under the passenger side of the dashboard to a lever. On mine that cable had been kicked off its retainer and was flexing rather than actuating the lever. It took about 5 minutes to look under the dash while moving the hot handle, identify the loose cable, and push it back into its retainer.

H'mm, so I'm 2 for 2. :bigok:

 

[fourwd1]

No, make that 3 for 3.