BMW 320D Auto - Smoke

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Fri 16 Mar 2012 23:38
BMW 320D Auto - Smoke - Woody37

I had a new Turbo fitted at 48K after a low speed failure.

3,000 miles on and I have two problems:

1. Economy has collapsed from 40 MPG urban to 29 and 60 MPG relaxed motorway cruising to 47.

2. Under hard acceleration a significant amount of smoke comes from the exhaust, to the extent cars even flash sometimes. I was told it might smoke for 1,000 miles post turbo failure, but this is 3,000 miles on.

I would say the smoke is blue and black.

The car burns no engine oil at all.

What is going on?

Edited by Woody37 on 16/03/2012 at 23:39

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Wed 21 Mar 2012 20:34
BMW 320D Auto - Smoke - Woody37

Bump. I would really appreciate some help please with this smokey BMW.

Is it possible for a diesel to "run too rich" or overfuel? It seems that at full throttle there is more fuel than can be combusted, hence the smoke.

It runs smoothly and certainly has some poke when required (kickdown) but economy has fallen markedly.

What might have changed?

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Wed 21 Mar 2012 20:52
BMW 320D Auto - Smoke - Collos25

You do not say how old the car is, older models (pre2004)suffer vanos problems and the butterflys disintergrating in the head along with various oils seal problems.I suggest you put the problem on one of BMW forums.

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Thu 22 Mar 2012 17:07
BMW 320D Auto - Smoke - unthrottled

older models (pre2004)suffer vanos problems

You won't find Vanos on a diesel engine.

It's more likely to be one of the classic problem of split intercooler hose or a clogged EGR valve/EGR vacuum operation.

Diesels can overfuel, if pressurised air escapes from the intake system after the MAF, so the ECU thinks more air is entering the cylinders than actually is. Split hoses are quite difficult to spot because they splits tend to only open up under pressure-which you won't get at idle.

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Thu 22 Mar 2012 15:52
BMW 320D Auto - Smoke - iworld

Try a product called Forte - apparently it clears ruibbish fromt the CAT and sorts out the mess - it cost around £13-£15 for a can

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