98 4.6 heat issues

[98ExpyinIA]

Replaced front heater core 18 months ago, both hoses are warm and not overly hot, when sitting air is cool and when driving it is warmer but not like it should be. position selector works for vent, defrost, etc but the temp control feels weird. no heat out of rear at all........

 

[rburch]

Could be a stripped post on the temp control knob. You could try to pull the knob off and see if turning the post has any affect.

 

[98ExpyinIA]

okay, temp control knob moves from cold to hot but feels like about 2/3 way just springs forward. front core hoses are hot/cold after starting and warm up, both are hot while driving, but when stopped for extended period one is hot and the other is cool to warm.... any ideas???