Hi,

Long time reader, first time poster...never had any major problems in the year I've owned the beast, until now. It's a 2004 545i and has 50 000 miles.

Yesterday I started my car car at work, it had been sitting for a few hours (maybe 3) so it was 'cool' and noticed a large cloud of white smoke behind the car drifting away and between there and another office the idle was up around 750rpm, I couldn't notice any more smoke while I was driving.

I kinda dismissed it, but when I went to leave the other office about 3 hours later I started it while I was outside watching and to my horror it did it again, a big cloud of white/*slightly* blueish smoke This time I tried shutting the engine off and starting it again immediately and it didn't do it.

I dropped by BMW and the foreman was thinking crankcase valves (I think he mentioned switching them from one bank to the other, then suggested they might just replace them).

Does this sound right? I'm kinda in shock that my 2004 BMW is blowing smoke...I'm not under a BMW service contract so I don't mind getting my hands dirty, is there anything I should be looking for?

Any suggestions would be very much appreciated!

Thanks in advance

 

sounds like a coolant leak. how are your fluid levels?

 

He may be right, but keep an eye on your oil to be sure there isn't any coolant contamination. Slightly bluish smoke tends to indicate some oil burning. White smoke is, of course, steam. Allow your SA to document, identify, and correct if necessary. Good luck - keep is posted!

 

Coolant getting into your exhaust is definintely not good and suggests at least a bad head gasket.

Keep an eye on the coolant level, if you see it drop or hear a gurgling sound whenever you turn off the engine then get it into a shop ASAP.

 

definitely coolant leak.

 

He's got it. Somewhere, somehow you've got coolant pooling somewhere while your car is stationary (on my Mustang, it used to pool in the intake and burn off when the valves opened). Then you start it and you get that big poof of smoke as it burns off.

The smoke with the slight bluish tint is oil. You might have some sort of leak that is allowing your coolant and oil to mix. When was the last time you changed your coolant? I know BMW says the coolant is lifetime but I've noticed that in prior cars, if I never changed the coolant, it would slowly eat away at the head gaskets and that would allow the coolant and oil to mix.

 

Thanks for the replies!

Haven't driven/looked her in the eye all weekend...so I will look into it tomorrow morning and check out the oil and coolant levels. The service guy said the oil was a bit down but that it's probably normal because of the 25k interval and it's due now.

I'm positive it's not steam because it doesn't dissipate fast enough.

I've got her booked in for the 20th because they don't have any loan cars but I might bring it forward and do without a car for the day while they look into it.

Thanks!

Thomas

 

You might have been seeing some condensation in your exhaust system blowing off ... maybe.

But to be sure you should definitely have a thorough cooling system pressure check. If a head gasket is leaking in the area of cooling system channels, on cool-down coolant could be sucked into a cylinder's combustion chamber. On the next start up the result could be deadly to your engine.

 

Well in true BMW form...it stopped blowing smoke up to when I took it in this morning for a service...and after I filled her up with petrol on the way the idle was normal and the adaptive headlights started working

Anywho....they replaced the PCV crankcase vent valves....they think it'll sort out the smoke, idle and higher than normal fuel consumption! http://www.realoem.com/bmw/showparts.do?mo...fg=15&hl=26 ....number 13

Fingers crossed!

Thanks for your advice

 

Good to hear, hope that is the fix...happy motoring