the car is 89 Cressida. Its ac works great but its heater in not. All the vents and controls work fine. Radiator is full of coolant. All I get is cold air coming out the vents. I?ve been working on this since last winter, I gave up now. So please help if you can. Thanks.
89Cress
Have you flushed the heater matrix? Checked its not bypassed? Bled the system properly so you dont have air locks? Checked the water control valve is connected and functional?
How do I flush the heater matrix? What is the proper way to bleed the system? Here is what I do: I jack the front end only up as high as the jacks can go, then run the engine, open the radiator cap, then fill with coolant when the level drops.
I check and I think the water valve is open or closed properly.
"89cress" wrote: > the car is 89 Cressida. Its ac works great but its heater in > not. All the vents and controls work fine. Radiator is full > of coolant. All I get is cold air coming out the vents. I've > been working on this since last winter, I gave up now. So > please help if you can. Thanks. > 89Cress
When you fill the radiator, do so with the car level, not up on jacks.
Flush the heater matrix (called a heater core in the U.S.) by setting the interior temperature to full hot while flushing the rest of the cooling system. Because of environmental laws, I recommend having the cooling system professionally flushed.
Set the heat to full hot and see if the heater control valve opens. If you are not sure if the heater control valve is moving, open the hood and follow the heater hose along the firewall to find the valve, and watch the lever on the valve move while someone changes the interior temperature from full hot to full cold.
AFAIK, there is no solenoid valve in the path of the coolant. The coolant flow is controlled by the hot water valve on the firewall.
The clicking sounds you are hearing are probably the actuators for the vent dampers and blend doors or relays for the fan and resistors. Even if the fan is not working, the heater valve should open.
Did you check to see if the heater valve on the firewall is opening and closing? Assuming it is, then is the return hose from the heater core warm or is it cold? Check the return hose to make sure it is not collapsed.
I am not familiar with this car at all, but is there a thermostat and did you check or replace it ?
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