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Auto Air conditioning ac, weird vapor or mist and light smell coming out of air vents. Any ideas ?
There is a mist or vapor, alike to breath in a freezer, it has a slight odor I can not describe it. A/C is still works perfectly, super cold, and the mist only comes out of the passenger vents. 1998 ford f 150 4x4.
I need some insight. anybody ?

p.s. thanks in advance for any help.

its possible its got a bad heater core in it and the mist your seeing is anti freeze coming out of it,keep an eye on the coolant level in it,if it's anti freeze,you,ll see it start to drop a little low,if that's it it'll must be replaced,it will get lots worse than it's now,good luck on it.

been a certified mechanic for 37 yrs.

if you have a vapor coming from the vents ans you say the A/C still works, im gonna say the heater core is bad, if its putting out a fog light mist

Normally mist is from wet outside air entering a cold, dry environment. If you have it on recirculation, and it does this, there's a problem with the vacuum system that controls the doors. If you have it on recirc, then switch to normal, it's a normal condition for mist to come from the vents. The smell, I could say is mold growth on the evaporator. To decrease this, simply run the fan only, no a/c, before shutting off the car. A minute or two will dry the evaporator core, and no mold will grow on a dry evaporator.
Hope this helps..
Yes totally forgot about the heater core, if the smell is sort of sickly sweet, as opposed to old socks type smell, then it may well be the heater core.

My guess is that you're losing an amount of coolant. there's a leak in the heater core and that's the mist that you're seeing. good luck.

PS Get it fixed, you do not want to breathe the mist it's a carcinogenic.

if it smells sweet it's antifreeze from heater core.time for substitute.