Please help me with a heating problem on 97 Expedition

[wavinwayne]

GA,

When the heater blows warmer as I described above, I have it on "panel" & the temp gage set to full hot.

I don't think it is related to the AC, but I could be wrong.

 

[Warstud]

There's a big list of possibilities when it comes to heating problems. Most of the time it's just a bad t-stat or heater control valve (if equipped). Flush the cooling system out and do reverse flush of the heater core. The radiator cap may need replacing or the coolant recovery tank hose may be plugged. Also the vanes on the water pump may be deteriorating and not providing enough flow. And as already mentioned a faulty vacuum line or cable or even blend door.

 

[Warstud]

"the air doesn't blow as cold as it once did, & the heater doesn't really get hot anymore. The hottest that the heater ever gets is what you would expect if the knob were halfway between hot & cold".

I guess I jumped to conclusions and missed this part. Have to agree with MATT_S and others: Blend door, Vacuum or Cable. Have the same problem with my Blazer.
It S*cks when your vehicle blows hot air in 90 degree weather. I found a way around that though. Good Luck!