Why is there smoke coming out of my air vents?

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Reese
Posts: 9
Joined: Sun Apr 01, 2007 10:24 pm
Car: 1992 240sx

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I was driving to work today and smoke just started coming out of my air vents, I had the AC running, and it was running fiine. The temp of the car was normal. I lasted for about 10 seconds and then stopped. what could be wrong?


silpena
Posts: 1052
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Car: Nis1993 san 240sx super hicas(wrecked)
soon to come to s-chasis
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maybe you have something stuck inside the vents or in the blower all those solinoides and wires and burn up stuff like leaves or could be just lint in the vents if their dirty.

funigui
Posts: 516
Joined: Tue Apr 10, 2007 5:44 am
Car: I HAD a 1991 240sx coupe. woked NA motor. ran like 14.5 ish. blew it up @ 140 after an ECU reflash.

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more then likely its just really cold air on a moist day, like you breathe in the winter and you see your breath.....only backwards.

killablue240
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Joined: Wed Apr 06, 2005 11:50 am
Car: sr powered s13 coupe, 1991 twin turbo 300zx

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did it smell like smoke? if yes your blower motor is probably saying bye bye,or stereo wiring possibly

Matej
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Joined: Thu Sep 22, 2005 3:29 pm

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Does it smell?

-Edit-killablue240 beat me to it.

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Reese
Posts: 9
Joined: Sun Apr 01, 2007 10:24 pm
Car: 1992 240sx

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It didnt really smell like anything, just a burst of smoke came out at one time, from the driver side vents, like the car was overheating in the engine bay or something and it was coming in the car vents but the car wasnt overheating weiiiird... I doubt it was my stereo wiring cause my CD player was on at the time, it still plays fine.

SpecDRacing
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Joined: Mon Apr 25, 2005 3:36 pm

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Sorry, but this one is too easy to pass up. What your getting is actually a miniature snow storm created by ice accumulating on the evaporator core. Basically, your R134/R12 (whichever) might be a little low, or your expansion valve is not working properly (I think they have expansion valves). Anyway, your pressures arent right. What is happening is:

As the air passes through your evaporator core (from the blower motor) it gets cooled by the evaporator. This cooling causes condensation on the evaporator. When pressures in the A/C system arent proper, or the refrigerent is low, you get an evaporator that acts like a freezer. The ice builds inside the evaporator then starts to break off and exit through the vents.

Thats the "smoke you see". It probably smells funny because your vents, ducts, and the evaporator itself have funk in them (best way to describe it...basically, dead skin, cat hair, dandruff, pollen, etc.).

10 seconds was probably just enough time for a patch of ice to break free and be blown through the system.

Get the pressures checked and the amount checked (lbs.). As for smoke from wiring, blower motor, etc...... In all my years as a technician, I have never seen smoke exit the vents from that type of problem. More than likely, it will exit the dash near the windshield. The blower motors normaly just die, no magic smoke.

Again, get the pressures checked and the refrigerent level checked. I'd bet thats your problem.

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Reese
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Joined: Sun Apr 01, 2007 10:24 pm
Car: 1992 240sx

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Thank you so much for the input, I was worried that it was something that might cause a damage to the car, if I proceeded to drive it. Would you recommend keeping the AC off till I get that checked?

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Morph
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Car: 91 Sr Powered Coupe

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Damn i would said it was poison gas and left it at that.

SpecDRacing
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Joined: Mon Apr 25, 2005 3:36 pm

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Its fine to drive. Dont worry bout it, it wont hurt anything. Glad to help.


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Reese
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Joined: Sun Apr 01, 2007 10:24 pm
Car: 1992 240sx

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that would be kinda funny if it was. someone trying to make me all woosy so they can take my car from me.

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okinawa drift
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technician ftw

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crash n burn
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Morph wrote:Damn i would said it was poison gas and left it at that.
ha ha..i was tossing up either crude jobe by your friends..or antrax....

Nick240sx
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or........i dunno cant help you here, just wanted to agree with the mini snow storm, that happened to me when i had my 240.


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