BMW 2002 E39 525 - loss of power and white smoke

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Sun 30 Jan 2011 17:35
BMW 2002 E39 525 - loss of power and white smoke - hazer

My wife's BMW 2002 E39 525 diesel appears to have intermittent starting problems

on the odd occasion the vehicle will not start.

if you leave it overnight it will start and appears to be OK.

my local garage thought it may be a fuel pump or injector fault.

This has happened about 3 times over the last 2 months.

but has recently developed a loss of power and is blowing out white smoke

but there is no loss of coolant any ideas would help

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Sun 30 Jan 2011 18:45
BMW 2002 E39 525 - loss of power and white smoke - Collos25

Have you had the swirl flaps removed if not you should with haste,you also appear to have a turbo problem.

http://www.bmwland.co.uk

Edited by Andy Bairsto on 30/01/2011 at 18:48

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Sun 30 Jan 2011 19:24
BMW 2002 E39 525 - loss of power and white smoke - unthrottled
White smoke on a diesel is normally unburned fuel-the most likely cause is ingress of air into the fuel pump causing low pressure injection. Turbos are inactive at start and low load and unless starved of oil generally work very reliably. I've heard about problems with BMW swirl flaps too. However, they are not extraneous components. Removing them will create smoke problems at low RPM due to insufficient air motion.
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Sun 30 Jan 2011 20:18
BMW 2002 E39 525 - loss of power and white smoke - Collos25

No it won,t.

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Sun 30 Jan 2011 21:26
BMW 2002 E39 525 - loss of power and white smoke - unthrottled

So why did BMW go to the hassle and expense of fitting a useless part? It's hardly a good marketing ploy since most customers wouldn't know a swirl flap from an egg whisk. Under full load/low RPM conditions you NEED swirl to get sufficient air/fuel mixing. 4 valve engines don't make sufficient air motion at low RPMs.

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Mon 31 Jan 2011 11:25
BMW 2002 E39 525 - loss of power and white smoke - Collos25

May I politely ask you to read about BMW swirl flaps a little more having removed these from my sons car it had no effect whatsoever on the performance did not create any smoke as it has on any BMW that has had the same operation performed.

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