i posted a few days back pics of my new truck.. 1990 gmc 1500. i love the truck, its runs and drives excellent. the one problem i have is the heat is blowing ice cold air. I went through all the obvious causes i know of. the engine temp is straight in the normal, so the termostat is in, I thought maybe when they installed the new engine this year, they bypassed the heater core... hoses are there, and in new condition. there are no leaks of any type on the truck. any ideas, maybe a sensor somewhere? the blower unit is working perfect... i can live without it ofcourse, but i would like to use this as my everyday ride also. should be something minor i'm sure, but i ran out of ideas.