When ever I turn on my defrost or my heater, all i get is ice cold air. Is my heater core out?

 

Check your coolant level if its low you'll only get cold air.

 

this guy has his head uphis butt. the coolant level is a good start but without coolant a host of other problems will manifest themselves and that is all i will say about that. checking the heater control valve is a start, but is the heater control controlled by vacuum or is it electrically contolled with position feedback and motor drives, I don't know!a better starting place would bethe vacuum res, the vacuum lines from the intake, or any associated hardware. then the hvac contoller, fuses, motors, feedback potentiometers and associated hardware. What contols the heater valve that flows hot water to the core? these are the questions you should ask! Get aervice manual(try ebay).