How do I fix The volcano inside my car - Toyota Nation Forum : Toyota Car and Truck Forums

jets1934 · 08-10-2010, 07:30 PM

I have search the treads for a solution so far none. I have 1993 Camry V6 XLE trim. I am getting roasted right now in the summer months here. The problem is that the heat is constantly on. I have replaced the heater control valve, the thermostat, the radiator was changed. It does not matter if the cabin fan is on or off, the dial swithch to cool or heat , outside air or recirculate, defrost/ upper, lower , combo. Hot air is always entering the cabin. The fans work great and switching to different zones work, I can feel it when I choose where the air comes from or goes.I have even changed and adjusted and disconnected the heater control valve..nothing..same results.car runs great, no check engine lights no over heating....anyone has an answer I would appreciate feedback..thanks

97ToyCar · 08-10-2010, 07:37 PM

The air mix damper control cable for temp adjust is either loose, broken, or out of adjustment. Pull your trim around the HVAC, and pull the radio out. Then you can access the adjustment cable. It has an adjuster clamp attached to it. The reason you are getting heat, is the air mix damper is not closing all the way. If I'm not mistaken it is on the left side of the HVAC assembly. Check with 73sport, he may know the answer, or can get some pics for you.

rusty9 · 08-10-2010, 07:51 PM

i would check to see that the cable hasnt come off the valve on the firewall. do you feel resistance when you turn the knob?

jets1934 · 08-10-2010, 08:08 PM

I have removed the cable adjusted the heater control and re-installed at least a dozen times still same problem..I have had that problem before and after i replaced all the items mentioned above...I will try the HVAC assembly..

jets1934 · 08-19-2010, 07:17 PM

Did all the suggested ideas..no more hot air coming from the top vents..after about an hour of driving I get get hot air blowing on the driver's side under the steering wheel only at the lower vent on the left. It doesn't matter if the vents are open or close..hot air is just pouring in...any more suggestions

***2wickedtoyz*** · 08-19-2010, 07:29 PM

bypass the heater hoses......then let us know what happens

73sport · 08-19-2010, 10:07 PM

Turn on the AC????

sorry, couldn't help it. . .

Does the AC on this car work?

I've never inspected this but perhaps the valve in the engine bay is defective? Yes the lever moves on the outside but maybe the valve lost some parts and hot water flows all the time regardless of its position?

Lets get some more details:

AC works yes/no?
Hot water cut off, feel the pipes they should be cooler when flow stops; y/n?
Diverter works, windshield, dash, floor, mixes?
Cabin mix vs Outside mix y/n?
Blower control works 1 - 4 y/n?

I suspect you lost control the diverter flap, like maybe something broke inside the heater box so its always getting access to the heater core.

AlmightyCamry777 · 08-20-2010, 11:12 AM

Quote:

Originally Posted by 2wickedtoyz

bypass the heater hoses......then let us know what happens

I think i'd do this. For a quick temporary fix, plumb in a valve to the heater hose so you can just shut off the coolant to the heater. That way you won't roast while you're working on the real fix.

jtex2717 · 08-20-2010, 11:34 AM

Some intense HVAC stuff here.....I am waiting to see the verdict...

jets1934 · 08-23-2010, 07:31 PM

ac-not charged, need freon , always off
on my second new heater valve control, different brands- same problem
diverter works perfectly, cabin mix/outside air works fine it even cool at night..but always blowing hot under the steering wheel as I drive..No holes in the firewall..
all blower speeds work..
I am so confused as to what the problem is..where is this hot air coming from and its only on the driver side not on the passenger side....?????????????

***2wickedtoyz*** · 08-23-2010, 11:25 PM

steering boot is leaking hot air or the leak is from where the heater hose is going into the car. both are on the driver side

73sport · 08-24-2010, 10:27 AM

Quote:

Originally Posted by 2wickedtoyz

steering boot is leaking hot air or the leak is from where the heater hose is going into the car. both are on the driver side

^^ could be, but doesn't he imply it blows with fan speed??

Take a look at this. The core issue is likely the damper as mentioned earlier. I'm guessing the lever doesn't move it so air is going through the heater core at all times.

Quickest fix is the heater bypass hose, just keep an eye on the engine that it doesn't over heat as the little core is helping to cool the engine.

Can you feel the difference in temperature at the water diverter under the hood. Do the hoses cool down when the flow is stopped?

Oh - pix is from AC.pdf pg 18 of Gen 3 Camrystuff.com

Edit Page 52 shows the correct position of the water valve to stop coolant flow which has the lever pointed downward basically forming a 90 degree angle between the cable and levers arm.

EDIT#2: Look at AC pg-58, it tells how to test the servo motor.