First gen no heat

Hey guys I have a 2004 Tacoma 2.7L and the heat is not working. I have tried many things and still no luck. First I replaced all the coolant but not a full flush just drained and filled the radiator. Then I checked the valve at the heater core removed it completely and found no gunk and the valve operated perfectly from the electric actuated cable. I put a garden hose through the heater core and water flowed out the other side as it should. I even blew into the hose itself and it kept flowing smoothly. Both hoses coming in and out the heater core ARE warm after running at proper temp. I then removed the glove box and radio to check the climate components. ALL climate actuators work perfectly as well as the blower fan but of course only blows cold. It appears the actuator that moves the cable for the coolant valve also attaches to a smaller piece. I think it is the actual blend door or just a pivot point for the mechanism. It moves only slightly but I’m not sure if that is it’s full travel or it is stuck. Am I missing anything here? My next step is completely pull the dash apart (that I would rather avoid) and visually inspect the heater core and check air flow through the vent where I think the blend door is actually located and maybe it’s stuck but I don’t hear any grinding or additional pieces trying to move. Any advise would help I’m going crazy and it’s getting cold out lol

 

Shoot the thermostat housing and before and after thermostat with thermal gun. See if motor is up to temp.... since you established you have water circualtion through the core, then I would think it would be no fan circulation through the blend door, should be fully open with total heat picked on the dial.

 

So I found the bottom hose of my radiator is cold. My mechanic friends tell me there is still air in the system or some minor blockage somewhere. Which is very possible because I’ve never pressurized the system or done a proper flush yet. The outlet hose from the heater core is also somewhat colder than the (very hot) intake hose. I squeezed every coolant hose I could find with the radiator cap open and could see fluid flow up and the occasional air bubble. So even though coolant DOES flow everywhere, there can still be air pockets and blockage? I got the heat to work for one single minute today and then stopped. I checked all the blend doors and actuators again and nothing is stuck.

 

Had any luck with a resolution for this? I have pretty much same issue... Thank you

 

Yeah turns out it was the head gasket unfortunately. Gasses from the combustion chamber were pumping into the cooling system. $3000 repair later everything works great! Had him do a whole new catalytic converter, motor mounts, and fuel filter while the motor was apart so wasn’t a waste. Recommend you do the same. The frame is practically brand new on this truck, the cost was worth it to me… Blown head gaskets can usually cause a lot of major issues but this was probably best case scenario. Engine continues to runs mint now with over 200k miles. Best of luck!