Heater blowing cold when driving
Aug 11, 2021 | 04:29 PM
#1
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Heater blowing cold when driving
Need some help here. My 96 taco is just blowing relatively cold air out of the vents. My temp control works. It isnt as cold as the air outside but its pretty cold. Ive replaced the heater core and thermostat. If I leave it on while not moving it gets pretty warm inside, not as hot as it should be though.
Aug 11, 2021 | 06:06 PM
#2
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From: I live in New Tripoli Pa out in the woods
Need some help here. My 96 taco is just blowing relatively cold air out of the vents. My temp control works. It isnt as cold as the air outside but its pretty cold. Ive replaced the heater core and thermostat. If I leave it on while not moving it gets pretty warm inside, not as hot as it should be though.
which engine ?
Do you have the AC on?
Is the valve on the firewall working?
Air set to fresh?/
Did you bleed the cooling system an air pocket in the heater core will cause your problem
Aug 19, 2021 | 01:45 PM
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I dont need the heat just yet hah, but this was a problem last winter basically in temps from 20 degrees down to -25 that we had last winter
2.7. A/C off. I havent double checked the valve Im thinking about just bypassing it though. Ive tried both fresh air and air from inside. Made sure blend door is good. I have not bled it now that you say that.
Also yes my engine temps are staying at normal temps at all times
2.7. A/C off. I havent double checked the valve Im thinking about just bypassing it though. Ive tried both fresh air and air from inside. Made sure blend door is good. I have not bled it now that you say that.
Also yes my engine temps are staying at normal temps at all times
Aug 19, 2021 | 05:13 PM
#5
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From: I live in New Tripoli Pa out in the woods
If you needed heat Now i am coming to visit!
Only 55 Degrees on Mount Washington Summit with a cool breeze 25 to 30 mph
Your not getting Hot Coolant through the heater Core to much dirt on the inside
or the outside not allowing the heat to be transferred out
Air pockets can cause strange things to happen
Only 55 Degrees on Mount Washington Summit with a cool breeze 25 to 30 mph
Your not getting Hot Coolant through the heater Core to much dirt on the inside
or the outside not allowing the heat to be transferred out
Air pockets can cause strange things to happen
Aug 20, 2021 | 11:59 AM
#6
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From: Chiloquin, OR
Your not getting Hot Coolant through the heater Core to much dirt on the inside
or the outside not allowing the heat to be transferred out
or the outside not allowing the heat to be transferred out
If the hose on the left, going into the firewall isn't as hot as the other, bad valve.
As Wyo said, you may need to "burp" the coolant system. Easy to get an air bubble stuck in the heater core(s). I, personally, park it nose high on a hill, so the radiator cap is the highest point on the system. I check the radiator and recovery tank for the right level of coolant, then only put the radiator cap on to the first catch, not all the way on. That way, any coolant or air coming out of the radiator will go out to the recovery tank without restriction. Any air will then go overboard, and the water will stay in the recovery tank. Set the heater control all the way to hot to make sure the heater core gets plenty of circulation. Start the engine, and let it heat up to operating temp. I usually run it for about 20-30 minutes.
Then using a heavy glove, tighten the radiator cap all the way down, and let it cool down all the way. A couple hours, at least. Check the radiator and recovery tank again for the right level of coolant.
Are you getting heat from the heater now?
If not, the core may well be clogged up with dust, dirt, etc, so no air goes through it. It goes around it if it's clogged. You might need to open the housing around the heater core to be able to clean out the fins. Use fairly low pressure air so you bend the fins over, and give it some blasts. You might be amazed how much dust dirt, etc gets caught up in the fins of the heater core. Once it's cleaned out real well, and all put back together, try the heat again.
Getting heat now?
If not, the core's water path may be clogged with corrosion build up. At that point, you may need to consider a new heater core. Don't forget to burp the cooling system again if you replace the core. Make sure to check the rear heater core as well.
Another possibility, if it seems like there may be an air bubble in the heater core, you can try a substance called Water Wetter. It lowers the surface tension of the water, like soap does, but doesn't allow foaming like soap does. The really makes the air caught in the heater core, or anyplace else in the cooling system, come out, and bubble out through the recovery tank. Just keep an eye on the fluid level in the recovery tank and the radiator. They could very easily get low as the air comes out of the system.
A small side note: Make sure to use the Toyota Red coolant, NOT the generic green coolant. It matters.
Keep us up to date on how things go.
Pat☺
Aug 20, 2021 | 01:43 PM
#7
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From: I live in New Tripoli Pa out in the woods
Check the heater valve on the firewall to make sure it's operating correctly. Let the engine come up to temperature, set the temp control on the AC Control Panel to hot, carefully touch both hoses going through the control valve. Or use a point-n-shoot thermometer. Anywho, both hoses should be hot.
If the hose on the left, going into the firewall isn't as hot as the other, bad valve.
As Wyo said, you may need to "burp" the coolant system. Easy to get an air bubble stuck in the heater core(s). I, personally, park it nose high on a hill, so the radiator cap is the highest point on the system. I check the radiator and recovery tank for the right level of coolant, then only put the radiator cap on to the first catch, not all the way on. That way, any coolant or air coming out of the radiator will go out to the recovery tank without restriction. Any air will then go overboard, and the water will stay in the recovery tank. Set the heater control all the way to hot to make sure the heater core gets plenty of circulation. Start the engine, and let it heat up to operating temp. I usually run it for about 20-30 minutes.
Then using a heavy glove, tighten the radiator cap all the way down, and let it cool down all the way. A couple hours, at least. Check the radiator and recovery tank again for the right level of coolant.
Are you getting heat from the heater now?
If not, the core may well be clogged up with dust, dirt, etc, so no air goes through it. It goes around it if it's clogged. You might need to open the housing around the heater core to be able to clean out the fins. Use fairly low pressure air so you bend the fins over, and give it some blasts. You might be amazed how much dust dirt, etc gets caught up in the fins of the heater core. Once it's cleaned out real well, and all put back together, try the heat again.
Getting heat now?
If not, the core's water path may be clogged with corrosion build up. At that point, you may need to consider a new heater core. Don't forget to burp the cooling system again if you replace the core. Make sure to check the rear heater core as well.
Another possibility, if it seems like there may be an air bubble in the heater core, you can try a substance called Water Wetter. It lowers the surface tension of the water, like soap does, but doesn't allow foaming like soap does. The really makes the air caught in the heater core, or anyplace else in the cooling system, come out, and bubble out through the recovery tank. Just keep an eye on the fluid level in the recovery tank and the radiator. They could very easily get low as the air comes out of the system.
A small side note: Make sure to use the Toyota Red coolant, NOT the generic green coolant. It matters.
Just why does it matter?? What Problems does it cause ?? All the cooling systems in the 22R/RE engines had the green coolant when The vehicles were donated to me ( Kinda forgot where this was posted?)
then I change the coolant it seems for one reason or another every few months Never an issue that I have seen Then the 55 gallon drum is about 1/2 full.
I use the Toyota Red in the newer 3.4 engines
Keep us up to date on how things go.
Pat☺
If the hose on the left, going into the firewall isn't as hot as the other, bad valve.
As Wyo said, you may need to "burp" the coolant system. Easy to get an air bubble stuck in the heater core(s). I, personally, park it nose high on a hill, so the radiator cap is the highest point on the system. I check the radiator and recovery tank for the right level of coolant, then only put the radiator cap on to the first catch, not all the way on. That way, any coolant or air coming out of the radiator will go out to the recovery tank without restriction. Any air will then go overboard, and the water will stay in the recovery tank. Set the heater control all the way to hot to make sure the heater core gets plenty of circulation. Start the engine, and let it heat up to operating temp. I usually run it for about 20-30 minutes.
Then using a heavy glove, tighten the radiator cap all the way down, and let it cool down all the way. A couple hours, at least. Check the radiator and recovery tank again for the right level of coolant.
Are you getting heat from the heater now?
If not, the core may well be clogged up with dust, dirt, etc, so no air goes through it. It goes around it if it's clogged. You might need to open the housing around the heater core to be able to clean out the fins. Use fairly low pressure air so you bend the fins over, and give it some blasts. You might be amazed how much dust dirt, etc gets caught up in the fins of the heater core. Once it's cleaned out real well, and all put back together, try the heat again.
Getting heat now?
If not, the core's water path may be clogged with corrosion build up. At that point, you may need to consider a new heater core. Don't forget to burp the cooling system again if you replace the core. Make sure to check the rear heater core as well.
Another possibility, if it seems like there may be an air bubble in the heater core, you can try a substance called Water Wetter. It lowers the surface tension of the water, like soap does, but doesn't allow foaming like soap does. The really makes the air caught in the heater core, or anyplace else in the cooling system, come out, and bubble out through the recovery tank. Just keep an eye on the fluid level in the recovery tank and the radiator. They could very easily get low as the air comes out of the system.
A small side note: Make sure to use the Toyota Red coolant, NOT the generic green coolant. It matters.
Just why does it matter?? What Problems does it cause ?? All the cooling systems in the 22R/RE engines had the green coolant when The vehicles were donated to me ( Kinda forgot where this was posted?)
then I change the coolant it seems for one reason or another every few months Never an issue that I have seen Then the 55 gallon drum is about 1/2 full.
I use the Toyota Red in the newer 3.4 engines
Keep us up to date on how things go.
Pat☺
Last edited by wyoming9; Aug 20, 2021 at 02:18 PM.
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Aug 23, 2021 | 11:53 AM
#8
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Joined: Jul 2005
Posts: 2,345
Likes: 656
From: Chiloquin, OR
Just why does it matter?? What Problems does it cause ?? All the cooling systems in the 22R/RE engines had the green coolant when The vehicles were donated to me ( Kinda forgot where this was posted?)
then I change the coolant it seems for one reason or another every few months Never an issue that I have seen Then the 55 gallon drum is about 1/2 full.
I use the Toyota Red in the newer 3.4 engines
then I change the coolant it seems for one reason or another every few months Never an issue that I have seen Then the 55 gallon drum is about 1/2 full.
I use the Toyota Red in the newer 3.4 engines
The red will also reduce scale buildup in the radiator and heater cores. Presuming you use distilled water, so it doesn't have the materials in suspension, needed to allow scale to build up. Although the green advertises that it reduces scale too, I am pretty sure the red does a better job by far. I am not certain about that, though.
The Toyota Red coolant is a bit more expensive, but I firmly believe it's a small investment for what you get in return. It's beneficial for the older 22R/22RE/22RET engines as much as it is for the newer engines, and for the same reason. Differential metal corrosion is a problem for Toyota engines, and has been since they started using the two metal engines.
Does all that rambling answer the question, or at least answer it sufficiently?
Pat☺
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