I have a 2000 Blazer . I know I have a leak in the heating/cooling system ...the overflow is always empty and I have to top of the radiator every couple weeks .. the water pump and thermastat where replaced a few years back ... .. The other day I was driving it and came to a stop ...the windsheild started fogging up and I turned on the defroster ... a vapor sstarted coming out of the defrost vents and the air vents ...I thought it was smoke at first . Never seen that happen before ...any suggestions ... it made a fine film on the windsheild that made it hard to see before I wiped it off ............. I'm lost on where to start looking for the problem ..... any help is greatly appreciated ......

 

You have a heater core leak.

 

Realy ? Crap ... and I bet it's buried nice and deep in there too .... Thank you for the info ...it is realy appreciated

 

Yes, it is buried! A search for "heater+core+replacement" should turn up quite a few results and maybe even a how-to.

 

Thank you very much ... I'll do a search and see what I find ........ Much appreciated ..... !!!!