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are both heater hoses hot under the hood???
there is no heater control valve.
both hoses are the same temp under the hood???
if all controls inside are working and you can hear the doors work back and forth, then the heater core may still be the issue. I would remove the hoses and use a garden hose to run water through both sides of the core to force any dirt out that may be preventing proper circulation. even though you see circulation it does not mean the core is clear.
ok, I still think your issue is at the core.
I will opt out and see if anybody else has any idea
We need to confirm that the water pump is in fact pushing water through the system. You can do this one of two ways get the engine up to operating temperature without the radiator cap on and see if coolant is being pushed into the upper tank and flowing through the radiator. The ideal way to do this is to remove the thermostat install just the gasket then hold the engine RPM at 2000 RPM and see if water is being pushed through the radiator very quickly. If it is the water pump can be ruled out. At that point reinstall the thermostat I know you run water through the heater core but 99% of the time that will not flush anything on the heater inside the vehicle. More than likely going to find that the heater core is clogged on most of the tubes. Even though you have flow it's only going to a few tubes versus the entire heater core. You will need to replace the heater core. If you're getting flow since the system is full of water carefully remove the hoses from the heater core, Then start the engine up and see if water is pumping through the heater hose going to the heater core. If it is then this rules out any type of restriction in the hoses or the block itself. That brings us back to the heater core again and it will need replaced.
You need to make sure that you have no air pockets in the block what I need you to do is fill the engine up completely without the thermostat and all the hoses connected. Hold the engine RPM at 2000 RPM you should see water flowing through the upper radiator tank when you look into the filler neck. If you try and pinch the upper radiator hose at that point you will feel the water rushing through the hose and it will surge out the upper radiator tank filler neck when you release the upper radiator hose.
If the impeller on the water pump was bad the engine would be overheating. It is not likely that the water pump is the problem. With the thermostat in the temperature gauge should rise up to about midpoint within five or 10 minutes of driving. The thermostat out the temperature gauge will be stone cold because there is nothing to slow the coolant down in the block.
Yes on the flow from the hoses to the heater core but have the tstat in it will push fluid that way to the hoses.
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