I recently purchased a 92 Accord, 213k. Everything works fine except the heater. The air is luke warm. I've replaced all the coolant and the thermostat, but heater is still not working correctly. The fan blows great and the AC is fine. When you first turn the heat on you get about a 20 second blast of real hot air, then is cools considerably. All the cables appear to be functioning, both under the dash and in the engine compartment. I see 2 hoses in the center of the firewall and i'm guessing the go to a heater core?

Do you think the heater core is bad? Looks like a bear to get to.

Thanks for any help! Much appreciated!
Mike

 

Yes those hoses go to the heater core, one should have the valve in it-please be sure it is opening all the way-engine side of the hose should be hot, then when valve is open so should the "other", firewall side.

Based upon your description (at least how I read it), I'd double check for air in the system (a blast of hot air and it stops). Be sure to have the heat set to max when bleeding.

Please check this before we go further.....if the heater core is not leaking, there are more options before replacing, which is a pain.

 

Thanks Poorman. I'll check the hoses and valve as you suggest. Appreciate your help!

 

make sure that the t-stat is working properly not sticking open or partially open,, also chk to make sure when it is all the way to hot from the heater control panel , that the heater valve is also all the way open to hot