93 Mark VIII no heat

[93mkviii]

Well a few weeks back I pulled apart my whole dash to try and fix the heat issue and found it wasn't the blend door. I checked the teeth of the gears in the blend door and also checked if the door moved with the rod inside the slot as i turned it by hand. Everything checked out fine. I get slightly warm air but not exactly hot. So the next thing would be heater core? But I've had this problem since 07' and haven't had a coolant leak or needed to fill it regularly so would that mean the heater core is fine? The thermostat was also replaced in that time since i've had the car for other reasons and that didn't change anything. I've heard of a heater core valve but can't seem to find much about it and everytime I search no heat in mark viii it's the blend door. Any place to start looking next?

 

[My Great 8]

Perhaps your heater core is partially clogged. Try removing the hoses and and blow water through it with a hose the opposite way of flow. My brother has an 88 Town car and had the same issue. He did this and it solved the problem. Good luck!

 

[chargerxr]

Definitely sounds like a plugged heater core. As Rich said remove heater hoses and blast water through going both directions several times. Should take care of it.

 

[Markviiiedrea]

A flush is easier then replacing a heater core, I would start there.