99 Civic Heat not working

[bml63]

I have a 99 Civic HX and the heat is not working in it. It blows air out but it doesn't get hot or even change temperature. It is full of coolant, I flushed the heater core, and changed the thermostat but it still doesn't get hot. I noticed that the heater contol cable that opens and closes the heater valve on the firewall doesn't move when you adjust the heat from hot to cold. I took the cable off and adjusted to the valve manually making it fully open and fully close but the air still didn't change temperature. Now I am all out of ideas so if anyone could help I would really appreciate it. Thanks.

 

[203CT]

ttt

 

[AlaskaB16]

Checked fuses and relay's? Let your temps get up and then touch the radiator outlet hose coming FROM the firewall. Is it hot? If it's not, your water pump might not be circulating. Heater core good? Does your rad fan turn on at idle?

 

[bml63]

The fuses and relays are good. The radiator outlet hose coming from the firewall gets warm after the car is warmed up. There aren't any symptoms of a bad heater core such as wet carpet or windows fogging so I am assuming it is ok. The radiator fan doesn't turn on when the car is idling though.

 

[ff4500]

I had that issue on my Jeep and it turned out to be a plugged heater core. No water inside of the cabin at all, just enough gunk in there that it only would blow luke-warm air out. Radiator flush wouldn't do much and flushing out the core with pressurized water helped a tiny bit. In the end, replacing the core was the way to go.

Check the radiator fan, as that may be an indicator of an issue if it doesn't come on at all.