Smoke/fumes coming from A/C vents???

[Fish Tale]

Anyone experience having smoke or fumes coming from their A/C vents while driving?  Doesn't happen all the time mainly during acceleration?  I am thinking it might be a heater core that is going bad.  My car is a 71 Cuda 383 with auto.  Thx.

[1 Wild R/T]

Heater core.... do your windows tend to fog up on cool mornings? 

[mopardave]

are you running the newer AC system like Vintage ? the evap could be leaking under acceleration pressure?? never really sean a heater core smoke. just condensation on the windows or the wet floor from the leak.

[Fish Tale]

The windshield has fogged up before.  I have not checked for leaks on the floor as of yet.  I guess it's more of a steam than smoke coming from the vents.  It doesn't smell like smoke.

[Fish Tale]

Also, it's not a newer A/C system.  Factory original.

[AARTA340]

With the symptoms you have shared, it sure sounds like a heater core has a small leak. You could isolate the heater core by disconnecting them at the fire wall and see if this stops the problem. You can just loop the two hoses together. Keep us informed what you find out. 

[Fish Tale]

I may just have to do that, thanks AARTA340.