why does it still blow cold? on 1991 Chevrolet S10

thermostat has been changed,hoses are all hot to touch,hoses out of heater core are both hot,cable style control inside of dash seems to be working( i hear flaps moving around)..what could it still be? its not like a dead winter cold that blows out of it, just feels like it has a tinge of warmth to it..just not a lot or enough to do anything really..

Asked by for the 1991 Chevrolet S10
your blend door could be sticking or broken
1 more answer
possible broken flap