Weird Looking Vent
 

i was wondering if someone knows why the dash vent by the pass side mirror has a funky geen thing going on, its a blue interior if that matters

Funky green thing? Mold? Post pics, please, I have no idea what you're trying to describe.

maybe someone put an air freshener in your car. and thats the remaining clip?

it looks like the vent fins are covered by oxidized copper

Most likely a leaking heater core and you're seeing the buildup of coolant and dust.... that or you've got lichen growing in your MKIII which would be interesting in its own right.

its only that one vent and i've seen it on other interiors

Post a damn pic already.

From what I've seen (including my own car), in cases of a small leak in the heater core more vapor flows out through that vent than the rest... if you look around you'll find old threads with people freaking about their ECU smoking often turning out to be due to dust and water vapor from a shot heater core.

holy crap.. ecu smoking. man thats a bad omen.

Got the same exact thing going on in my Supra. Same place - same color interior. Oh well - I need to pull the dash out too! Could a small leak cause me to continually get air trapped in the coolant system? Every time I think I get rid of that waterfall sound it re-appears again?

Yes, the waterfall sound is due to air in the cooling system; You're losing coolant somewhere. When you turn the heat on on a relatively warm day, do the windows promptly fog up? Check the carpet where it sits up against the firewall for moisture in both the passenger and driver's foot wells.

I'd still like a picture of what you folks are seeing... I didn't have anything like that when my heater core went, but perhaps I just replaced it too quickly. Is the green stuff damp or sludgey?