Smoke from air vents when I turn on the A/C

I just acquired a 1995 525i. I turned on the A/C, but didn't feel any cool air. After about 5 minutes, smoke suddenly started spewing from the vents.

So I shut down the A/C and fan. I didn't see anything else wrong, so I continued driving home. I could still smell the smoke on me later.

I don't see any fluid (athough I do have a oil leak from the valve cover gasket and have been smelling that as it's evidently dripping on something hot).

Thoughts?

Reply to
cowznofsky
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Odds are it's your blower motor burning up. A combination of moisture in the windings over the years causing the insulation to break down, and the motor being dragged down by bearings that haven't been lubricated will cause the motor to overheat and smoke.

Once it's done this it's too late to clean and lube the bearings, it's usually time to replace the motor. Sometimes it'll make squealing noises for a while before it goes, sometimes it just goes.

I don't know how hard it is do to on your vehicle... on some models of that era it's very easy to get to the AC fan and on others it is a nightmare involving removing the dash.

The other possibility is the resistor pack.... but that usually produces only a little puff when it goes, and afterward the fan will work only on high speed, or it cannot be turned off, or something like that which is clearly related to the speed control.

--scott

Reply to
Scott Dorsey

ouch. I think it's burnt. I still get the burnt smell even though I've kept it off.

Reply to
cowznofsky

Get a replacement from the dealer for around $50, and then get the Haynes manual and see about changing it.

As I said earlier, on some models it's very easy to do, and on some models it's very difficult, and you won't know which until you try it.

--scott

Reply to
Scott Dorsey

in article snipped-for-privacy@v15g2000yqn.googlegroups.com, cowznofsky at snipped-for-privacy@yahoo.com wrote on 4/13/09 4:10 AM:

the smell is in the heater/condensor core ... the outside air passes through it with the heat or the A/C on ... and the back fire tainted the heat exchanger ... put burnt oil film on it.

There is condensor cleaner for the A/C to take smells out of it .. some actually clean .. others just put a better smelling oil on it.

If you take it in for service for the A/C if you do that ... they might be of help.

sumbuddie wear blind sea

Reply to
Alan B. Mac Farlane

Hmm. Maybe so. It's in the shop right now for the oil leaks, and they say that the blower motor is ok.

Reply to
cowznofsky

AHA! You didn't mention that the car had an oil leak.

IF the engine has an oil leak near the top, and it spills oil onto the exhaust manifold, it will make a lot of smoke in the engine compartment. Leaky valve cover gaskets are popular sources of this.

If you have the heat or AC on and it's set to take in outside air, it will take in smoky air from the engine compartment.

If this is the case, though... you'll also see smoke from the engine compartment... just little wisps. And the REAL thing is that the smell will be a burning oil smell, not a burning plastic kind of smell. Very different smell, and the mechanic should be able to sniff the residual odor and let you know.

--scott

Reply to
Scott Dorsey

in article gs27s6$jhe$ snipped-for-privacy@panix2.panix.com, Scott Dorsey at snipped-for-privacy@panix.com wrote on 4/14/09 7:50 AM:

yeah ... if you are ever driving, and come to a stop ... AND you see some little wisp of blue gray smoke come up ... have then take a look for an oil leak.

with these aluminum block engines that are machined so carefully ...

any oil leak on the block will make them warp from uneven heat expansion.

it trashes the engine over time ... to save a few pennies.

of course do not EVER buy a used BMW with an oil stained engine.

Same for helicopters and airplanes.

Remember ... politicians like diapers must be changed often

sumbuddie said dis

L:?

Reply to
Alan B. Mac Farlane

m

Well, that's terrible news. I had it in the shop, and they replaced the gasket, and it still leaks. So now I just now took it back, but this is scaring me.

Reply to
cowznofsky

What gasket did they replace and where does it leak? Are you going to tell us the whole story or it is just going to keep coming out in little drips and drops?

--scott

Reply to
Scott Dorsey

Ok. Well, first of all, you'll note that I did indeed mention the oil leak in my original post.

Moving on, I had the valve cover gasket replaced. The shop also replaced the grommets and also had to replace the plugs and the seals (or whatever they are) around the plugs, since the plugs were soaked in oil. I was very impressed with the guy at the shop and had a good feeling about the whole thing.

So I drove the 5 minutes back to work, and saw it was still leaking. Left the car back at the shop this morning, and then saw the post about possible engine damage and my insides started churning. I called the shop and they said the leak was from an oversight, that a seal hadn't been fixed correctly.

But I haven't yet picked up the car again.

Reply to
cowznofsky

Makes sense. If you have hydraulic lifters and don't have to pop the valve covers every once in a while and put a new gasket on in the process, eventually the gaskets and seals will go bad just from age.

Makes sense... it's very easy to not seat one of those rings properly. You should be fine.

--scott

Reply to
Scott Dorsey

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