There is smoke/steam coming into my interior through the defroster vents. I am not sure if it is smoke or steam, but it's a very light colored, thin vapor that smells like my cats breath (I know that doesn't help you) that's leaking out of my defroster. I have no idea what would be going on in my dash that would cause this to happen, so I'm hoping someone here will know. My defroster doesn't have to be on for it to do this.

Have you checked your heater core? I do not know what a cat's breath smells like since I am a dog person, but I would start there.

Where is the heater core? If you dont feel like telling me then you dont have to.

I would guess heater core as well. I've never changed the heater core in the fiero, but in every other car it is located behind the glovebox above the passengers feet. Check the carpet and see if it is damp, that is usually a dead giveaway of a leaking heater core.

I have seen where "fog" comes into the cabin through the vents from the AC cooling humid air.

The heater core is a small radiator under the dash, hot coolent gets sent through it and when you switch on heat, air gets deflected through it and that is how your car is heated. They have a tendency to leak as the Fiero ages, but the oder is more like the smell of coolant, rather than cats breath.

I'm with the others. Sounds like you're blowing coolant fumes out of the vent.
If you have antifreeze in your system, it'll have kind of a sweet smell, and it will tend to make a mess on the inside of your windshield.
If you don't have antifreeze in your system, it'll probably smell like rusty-azz water.
I, also, am more familiar with dog breath than cat breath. Sorry.

quote Originally posted by MordacP: Where is the heater core? If you dont feel like telling me then you dont have to.

Well... I dunno.
Do you know the secret handshake?



All kidding aside... The heater core is under the right side of the dash, inside the end of the black housing. If it's leaking, I also wouldn't be surprised to see coolant dripping from the seam in that housing, where the cap is screwed on.

Here's an excellent writeup on how to find and replace it.
The last one I bought was ~$24. I think they're up in the $30s now.

//www.fiero.nl/forum/Forum2/HTML/043997.html
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Raydar
88 4.9 Formula IMSA Fasback..........................88 3.4 coupe -soon to be something other than red

Read Nealz Nuze! Praise the Lowered!

[This message has been edited by Raydar (edited 09-16-2007).]

Check to see if the carpet is damp on the passenger side (feet area).It's either water or smoke and you would probubly know the smell of smoke.I agree, probubley heater core (looks like a 10 inch radiator)I think it's removed from the bottom of the pasenger side kick panel.

Another source of smoke in the HVAC system is leaf and debris buildup in the air box underneath the grill in front of the windshield. There's a resistor pack in the air flow that will get hot enough to ignite dried leaves. Do a search for "blower resistor" and you should get lots of hits on how to clean the debris out and check for this problem.

JazzMan

My car would every once in a while just start smoking out the vents like the car was on fire. First time it scared the hell out of me. It ended up being the blower motor, it would work just fine then all at once, it would smoke like crazy.

There are 2 types of heater cores also. With A/C and without. The ones without A/C take about 30 minutes to change. Those with A/C take longer. (if it's leaking and not the blower motor or resistors.)
Here is a pic of the front compartment showing resistor and blower location:. The heater core is behind this area.

I can change the a/c version heater core in 30 minutes, because I did it at lunch one day and still had time for a nice lunch.

JazzMan

The "cat's breath" comment is a definite heater core. Sometimes old coolant can take on a "fishy" smell. I have had one cat in my lifetime (the EXXX- wifes) and her breathe always smelled like fish (the cat's too).

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carpe diem