quick back story. i have a 88 suburban it was having heater problems and i read on another thread that it might be the heater core. when i went in to change it out i noticed that the lever that controls the temp i guess was not sitting properly so i went in and moved it back to where it was looked like it was supposed to be. i let the truck run for 30 mins with the heater on and i noticed that the air got worm in my frustration from dealing with other things on the truck i stomped my foot and hit the gas pedal by accident when i did that the heater started blowing hot air. now my question, is that how its supposed to be or should i just go ahead and put the new heater core in there?