Two words: Heater Core.
Does it smell like anti-freeze? Is it hard to wipe off the windows? Is it there now each time you turn on the defrost? Is the carpet wet in the footwell of your passenger side?
Big Chris
Amy wrote:
Hello there. I had quite a scary problem driving to work this
> morning. I reached over to turn on the vents in my 92 Chevy s10 and
> instead of air, I got a nasty, sweet-smelling vapor that poured out of > the vents.
>
> What on earth could it be ? I tried checking the fan and the fan
> belt, but they seemed to be working fine. I lifted the hood while the
> car was running and there is no smoke inside the engine area; it
> seems to be comming from inside the dash somewhere. Any ideas on what
> might cause this ?
>
> Amy Boyd
> amy snipped-for-privacy@nail.com