Smokey BMW 2.0d - lots tried already. HELP Please

[lord trumpton]

Ok Guys

Could do with some expert input here please. Here is the lowdown

Detail

BMW X3 late 2004.
68k miles (genuine)
Non/pre DPF model

Problem

Smokey (black) upon hard acceleration
Smokey when rpm really low and floor it - when the boost starts to build it smokes
Normal, easy driving - fine
At idle - fine
Seems a touch laggy when accelerating but does pull OK when boost arrives
Turbo - with window down there is a nice, crisp whistle (normal imho) from turbo.

Things recenlty done

Codes read - nothing significant
Inlet manifold and EGR removed and cleaned
New glow plugs and module fitted
air filter changed
upgraded oil breather/separator fitted
fresh engine oil

Any more suggestions chaps? I'm pretty Ok with the spanners and all above done by myself - `it would be easy to just take it to a garage but `i want to get to the bottom of this myself

Many thanks for taking the time to read the lengthy post

[S0 What]

I'd check all the boost hoses carefully, it could be a simple small boost leak, you may hear the leak when it's on boost but it could be a split that only opens when in gear and the engine rocks ?

[lord trumpton]

Thanks for the reply

Surprisingly I overlooked a oily output hose on the intercooler; sounds like something amiss there

Would a boost leak cause black smoke? As I understand black smoke is due to excess fuel?

[LordLoveLength]

lord trumpton said:

Would a boost leak cause black smoke? As I understand black smoke is due to excess fuel?

If the leak is *after* the air measuring then yes. ECU thinks more air enters the engine than actually does and adds a corresponding fuel amount.

[lord trumpton]

Thanks for the help

It was the output boost pipe on the intercooler. I removed and cleaned up and replaced the internal rubber seal.

Now running like a dream.