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..
why does it still blow cold? on 1991 Chevrolet S10
possible broken flap
your blend door could be sticking or broken