Expert: Skip Bollinger - 9/6/2006

Question
when i turn on my heat i see vapors from burning radiator fluid and sometimes when niether the heat or a/c is on, the same thing happens.  

Answer
Philip,
  I have told the kind people at All Experts I'm a parts professional, not a tech but your car is getting close to the vintage I USED to work on. I even have a book that shows how to fix it!! Now to your question...
   You didn't say where the vapors were coming from but I would guess the defroster ducts?? You didn't say if the engine was warm or if it happend the minute you start the car but I would imagine it has to be warm??? IF SO...
  What you are seeing is steam. Does it smell sweet?? Check the carpet on the passenger floorboard. Is it wet? Is the coolant low? Do you have to add antifreeze?? It sounds like you have a poor connection where the heater hoses attach to the heater core (probably not) or (more likely) the heater core has kicked the bucket. IF this is the case, here is how to fix it. I'm quoting from "Motors Repair Manual", Product Number 16852, ISBN # 0-87851-670-0 dated 1989, General Motors section, page 3-15. That was for the legal mumbo jumbo. Sorry.. Here we go:
"1.  Disconnect battery ground cable and drain cooling system.
2.   Disconnect heater hoses from heater core. Plug core outlets to prevent coolant spillage.
3.   Disconnect wire connectors, then remove front module cover attaching screws and cover.
4.   Remove heater core from module, Figure 20. (which you don't have).
5.   Reverse proceedure to install." End of quoting.
   From Figure 20, it appears that the "module" contains the blower motor and the heater core. It looks like a piece of cake to change. I would guess only 2-3 beers, depenging on how many friends you have helping.
  When you go back together with the housing, be sure to put some silicone sealant between the fiberglass heater module and the firewall. That way it won't suck ambient air into the system.
  Philip, I hope this helped. There is NO other thing I can think of that would cause vapor to escape from the vents in your car. Let me know how it goes!!
Skip
CarPartMan@aol.com