Smoke

[C11 mbu]

Hello guys

Yesterday while I was in the drive through queue at mcdonalds, my x started to smoke quite badly, smelling of burnt oil or something .. Pulled off and floored it , huge trail of smoke and then nothing .. All ok until I'm stopped in traffic and the same thing happens.. Should I be worried?

Cheers
Wayne

[X5Sport]

In a word.....yes.  Any unusual smoke needs tracking down.  Blue/Grey smoke is usually oil, black is fuel.  Diesels will also produce grey/white smoke if it's un burned fuel in large quantities.

Not sure which version/year you have so it could be any number of causes.

Richard

[C11 mbu]

Hello mate, thanks for the reply,

Mines a 2005 3.0d , I had heard it might be un-burned fuel but wasn't sure, like I say it only happens when it's been stood for a couple of minutes on tickover so hoping this is what it is

Wayne

[X5Sport]

Any loss of power?  Excess fuel consumption, misfire?  You should not get any smoke at all after tick over except possibly steam on a very cold day, and black smoke when you boot it.  Fuel injection only gives enough fuel to keep the engine running - or should - at tick over.

Breather changed?  If not then definitely worth doing and is a DIY.  It might be blocked and at low revs the pressure could be forcing oil into the air stream/past a turbo seal.  This can lead to turbo failure.

Any indication of unusual sounds from the turbo?  Might be worth having a look at the air path to make sure there is no oil in the plumbing or inter cooler.

How is the oil level?  It should use oil, up to 1 litre per/1,000 miles at new though this drops as they get older.

Richard

[C11 mbu]

Hi mate

Thanks for taking the time to reply.. It's funny u should ask about turbo noise, thought I heard a really high pitched noise when I floored it trying to clear it but wasn't sure , breather ?? What is this ? Sorry for sounding dumb lol

Cheers Wayne

[X5Sport]

High pitched whistle is fine.  Grinding noises aren't.

There is a breather/oil separator on the top of the engine which in 2004 is likely to be a foam 'bog roll' design and known to cause issues with engine breathing to an extent that the crankcase over pressurises and it can (in the worst case scenario) cause oil to leak past the turbo seals.

The fix is to replace it with the later model of vortex device that does not clog.

There are threads on here on how to change it, but simply it is no worse than removing the BMW engine cover, fuel injection electrics fixing screws and another four screws to replace the complete unit.  Cost is about £50 and takes about an hour.  You can also replace the air filter at the same time as most of the same stuff comes off.

Richard

[X5Sport]

Main thread is here.

It's very detailed and tells you all you need.

Richard

[C11 mbu]

Richard ur a diamond;) thanks for the help, much appreciated

Wayne