My wife's 2005 Equinox heat has not worked for a while. Occasionally, it will get luke warm, but never truly hot. I have done a few things to fix the issue:

1. Replaced the thermostat

2. Went in to see if the blend door was the issue, but I noticed two things. There is no electronic actuator, it looks to be cable driven and it is definitely working correctly. I can feel and hear the blend door moving, as well as, hear and feel the difference in the airflow as it moves.

Are there any other things to look into? Has anyone flushed out the heater core and had success?

Any help is appreciated.

 

Could be alot of things wrong, like:
Plugged Heater Core: This will not allow the coolant to flow through the core causing poor heat. To check for this problem it is simple. First you will want to take your hands and hold on the two heater hoses going to your heater core. These are located by the firewall. Since your vehicle is warmed up they both should be about the same temperature and hot. If one is not hot then you have a plugged heater core. If you have a plugged heater core this could come from sealants being put into your radiator. You may be able to clear the debris however. You will want to remove the two heater hoses and take a garden hose, and spray into one of the hoses. Hopefully the water will clear the system. If not, then you may have to take your vehicle to a mechanic and have them try further.

 

Hi, follow the return hose from the heater core. The one hose will have another smaller hose coming from it going to your over flow tank. Make a reducer to restrict the flow, don't close it right off just restrict it. You will get more flow going through your heater core directly from the engine, see how that works for you.