when i turn on the defrosters everythign works fine defrosts the front windsheild but when i turn on the heat on the floor or the dash vents there is a smell of coolant and a puf of what looks to be white smoke or sum sort of dust build up and the windsheild will fog up almost instantaniusly my guyess is a heater core any other things it coudl be

 

the heater core is most likely leaking.

 

thanks thats what i figured ony reason i was second guessing is when its the heater core dosent it leak onto the pass side floor ?

 

just a small leak?

Im sure NGM will be more than able to help you if you make sure to give him all of your info.

 

The coolant is caught in the same pan the ac drains into. Look for a coolant stain on the ac drain. IF the ac drain is restricted or its a BIG leak on the heater core then you will see it on the passenger side.