Auto Air conditioning ac, strange vapor or mist and mild smell coming out of air vents. Any ideas ?

Question

There is a mist or vapor, similar to breath in a freezer, it has a slight odor I cannot 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... anyone ?

p.s. thanks in advance for any help!

Answer 1

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 is anti freeze,you,ll see it start to drop a little low,if that is it it will have to be replaced,it will get a lot worse than it is now,good luck on it.

Answer 2

Normally mist is from humid outside air entering a cold, dry environment. If you have it on recirculation, and it does this, there is a problem with the vacuum system that controls the doors. If you have it on recirc and then switch to normal, it is a normal condition for mist to come from the vents. The smell, I would say is mold growth on the evaporator. To reduce this, simply run the fan only, no a/c, before shutting off the vehicle. 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.

Answer 3

Auto Air Conditioning Vents

Answer 4

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

Answer 5

My guess is that you are losing an amount of coolant. There is a leak in the heater core and that is the mist that you are seeing. good luck.

PS Get it fixed, you don't want to breathe the mist it is a carcinogenic.

Answer 6

if it smells sweet it is antifreeze from heater core...time for replacement...