White Smoke/Steam

[Golgade]

Hello,
I know this gets posted alot, but my car smokes alot or should I say steams. Now it very white smoke, and it happens no matter how long I drive it but it is also very erratic. It does seem to go down some after it warms up but it still varys. For example Yesterday I came up to a stop light after driving for about 15 mins and pull away only to see a very large cloud of smoke obscuring the car behind me, then later I was driving back (after a good hour of driving) and stopped again and there was still smoke but you could only see it if you were looking in the side mirror at the ground. Then later again there was no smoke. Then later again I was at another light with smoke levels somewhere in the middle. I dont really know if I am loosing coolant or not because I dont really know when to is a good time to check. The levels seem to vary up to 2 inches in the over flow. Any advice in what I should check for? I just hope i dont need a new head or head gasket, but we will see. Oh a is that hose at the top of the coolant overflow a boil over? (meaning I guess does it go no where)
Thanks
Dan Lafley

[shogun]

That is normal.
'The levels seem to vary up to 2 inches in the over flow'
depends on the temperature of the coolant, therefore there is the expansion tank.

'Oh a is that hose at the top of the coolant overflow a boil over?"
the cap of the expansion tank has a pressure relieve valve. That is to avoid overpressure. I would recommend to change the cap in regular intervals, for example very few years. There was also a recall on defective caps.
Yes, there is also this overflow connection next to the cap on the expansion tank. That drops down under the car.
Best way to test:
in your garage or parking lot, every morning after the engine cooled down for several hours completely and the car is in the same position. Not in different place. The lower part of the expansion tank is the white/milky plastic, there you can see the level without remocing the cap, there is also a mark for the normal level. Have a close look at that.

[632 Regal]

whats the ambient temperature there?

[Golgade]

I did just change the coolant and I accidently filled the coolant level all the way to the top of the overflow tank. Then I drove it a few day but never more then 1 mile, and the coolant level stayed the same. One day I took it out for about two hours and checked the coolant the next day and noticed that the level had dropped about 1 inches, and I started freaking out, but I had thought about the fact that it probably boiled over because of the amount I put in. I havent really been driving it since but should I expect levels to drop until it gets to normal level? Also the temp here is usually about 38 - 45 when I drive in the morning.
Thanks

[Tiger]

That white smoke is unburned gas combusted by the cat converters. To fix this, change the spark plug and the coil pack boot... it is the coil pack boots that is at fault here... it let electricity stray out and thus not provide enough spark power.

I had this problem too.

[Omega]

That white smoke is unburned gas combusted by the cat converters. To fix this, change the spark plug and the coil pack boot... it is the coil pack boots that is at fault here... it let electricity stray out and thus not provide enough spark power.

I had this problem too.

Really? Has anyone else heard of this?

I know my BM dumps white smoke like it's going out of fashion when it gets cold and I often wondered why it is that BMW's in general smoke more than other cars.

I put it down to water/steam in the exhaust but you could be right. There is a hell of a lot of it and it does linger for ages, even when the motor is warm.

Any comments from our estemed guru's? 632Regal > sit down.

[tim eh?]

Any comments from our estemed guru's?

tiger's not an esteemed guru?

[Tiger]

Tiger is only a cat...

[BMWDriver]

Cold weather seems to bring this subject back every year. Though I kept a lookout recently, this year seems to be less in my case.

When I had my water pump replaced, the non BMW indie filled up the coolant to the top. But I went out of my way to take it back down to it's normal level when I saw this. The message "COOLANT LEVEL" had come up, to my surprise, after driving off with the new water pump. As old as the car is (sweet 16), I don't want to tax its coolant system if it can be avoided.

[Dave M]

That white smoke is unburned gas combusted by the cat converters. To fix this, change the spark plug and the coil pack boot... it is the coil pack boots that is at fault here... it let electricity stray out and thus not provide enough spark power.

I had this problem too.

This would be a very expensive way to troubleshoot a normally operating engine/exhaust.

These things have huge exhaust systems (volume) and will accumulate a lot of moisture which takes time to evaporate. If you're not using coolant and you're not getting crap mileage, forget about it.

Without a cat (tisk tisk) mine blows loads of steam. Liek a choo-choo. Chuga chuga woo-woo............

Dave