2006 Allure - Heater issue

Out of the blue, my wife's car stopped pumping heat out of the heater. First thought was the thermostat. Changed it and bleed the system, but still only a bit of heat coming out. Car's gauge shows the temperture as normal (just under the half way mark). Her car is the higher end version with the electronic controls. Is there some common issue that can cause this? Fan works / blows fine, just next to no heat comes out.

Before changing the thermostat, was the coolant level low?

With car at normal operating temp, command full hot....if no heat, feel the inlet and the outlet hoses to the heater core....if outlet is cooler(both should be hot), then the core is partially plugged and should be reverse flushed to try and get the crap out of it....

If both hoses are hot, then you have to check the actuator for the temp door.....command full hot to full cold and back and see if the actuator moves...

Thanks for the reply. Coolant wasn't low prior to thermostat change. All was normal. I'll check the heater core hoses and see what I come up with and report back.

Checked the lines, and one is hot and the other is warm. Do you know by chance what size the lines are so I can buy a length of hose to use to flush the core out? I assume I can just flush it with a regular hose / water...

They do make vice grips for hoses...can clamp off both lines, to reduce the mess....should have a pan under the car anyway......then, remove hose clamps and with both hoses off, measure the OD of outlet tube and get a short piece......you can just try reverse blowing throw it......but watch out for the stuff coming out of the inlet tube...if you want, you can get a hose for that and aim it into a jug or the pan below....

when clear should be able to blow BOTH ways, very easily....reattach lower hose....remove vice grip/clamp from lower hose.....may be enough pressure in system to fill and it will come out of inlet....if it does immediately attach the other hose.....remove vice grip/clamp from inlet hose.....now you can burp that hose for any remaining air.....attach both hose clamps...check radiator and reservoir level.....top off if necessary....run vehicle.......when cold, recheck the radiator and reservoir level again and top off....

If there wasn't enough pressure to make coolant come out of the inlet tube, just attach the outlet hose and hose clamp.....get a funnel and insert your hose to the inlet tube and add until you see coolant(recommend clear hose) build up......then remove and immediately attach inlet heater core hose and hose clamp....