white smoke from exhaust

[jasper69]

I have a 2002 325ci with just over 100k miles on it. When I drove it home about 48hrs ago everything was fine. When I took it out today I noticed in my rearview that there was alot of white smoke. By the time I turned around and got back to my driveway, there was ridiculous amount of white smoke and the car stalled as I pulled in. I let it sit for a while and tried to start it again. It was difficult to start and I had to push the gas pedal all the way to the floor to get her going, similar to the time when my floormat was pushing up on the gas pedal before I started it causing the injectors to flood(?). Anyway, I checked my coolant and it wasn't low. When I checked my oil, as I removed the dipstick, I heard a hiss come from the tube as if there were pressure built up in there. I then let it sit for a few hours and the car started normal without any smoke, however within a few minutes and a couple of revs of the engine, the smoke came back.

Any thoughts? I really hope it isn't a head gasket. The hissing sound from the dipstick tube...could that mean it's the crankcase vent valve?

[nathancarter]

Sounds like maybe a dying crankcase vent valve (aka Oil Separator, PCV, etc). This is a relatively common problem and a relatively easy fix. But, a dying PCV would be dumping oil into your intake, which generally causes blue-ish smoke (white smoke indicates coolant, black/gray smoke indicates unburnt fuel or carbon). However, I'm not sure if synthetic oil gives the same blue smoke as conventional/dino oil.

Try this:
With the engine at idle, remove the oil fill cap. How much suction is there under the cap? Does the engine stumble as you remove the cap?

You can also pull the spark plugs and see how they look. Ideally, you'd pull all six.. if all six are oily, then maybe it's the PCV; if only one is oily, then maybe it's a bad head gasket that's leaking into that cylinder.

[jasper69]

thanks for the reply. It's at bmw now and it was the oil separator valve. $750 to replace and another $250 if I want the insulated dipstick tube. What a ripoff.

[bmwill831]

this issue is most common in colder climates, right? I live in santa cruz and it never gets below 30 here, but is usually in the 50's in the middle of winter

[nathancarter]

More prevalent in colder climates, but can happen to any car that is rarely run long enough to really heat up the oil and let the moisture in the oil burn off.

[WHITEXi]

Dying ccv/pcv. Mine did the same thing it was a thick white smog type smoke, I got the parts which is a pcv valve $40 bux and 4 hoses which were $100 bux and im haveing it put in as we speak. I would expect a blue smoke to for oil but I think the synthetic dosent smoke from what I was told.

[jasper69]

I just recently got a job that is alot closer...about 10 to 15 minutes drive time. Probably had some condensation build up. Now with the snow storm we just had causing my car to become a block of ice, it probably froze up.