Diagnose my BMW 320d - black smoke at low rpm

[Station]

Embarrassing, especially at night with headlights behind you.

At a standstill, I can pull away as slow as possible and I get a plume of diesel smoke.

I've changed the Turbo, cc filter, injector, etc and now stuck.

The car had a blocked cc filter six months ago, I changed the turbo and filter, and it cured the GREY smoke and have now put up with the black smoke for long enough.

Flooring it also produces a large smoke screen.

Car was running rough a couple of months ago, and INPA said injectircwas knackered. I changed the MAF, injector #1 and charge temp sensor (it didn't have one!), and it went away for a couple of days but now it's back. EGR has also been capped off as I was getting bored of cleaning the back log out of the inlet.

Car itself drives perfect, it's s really nice car, but I'm in the verge of p/exing it for a Merc.

[Guest Hooli]

Black smoke is excess/unburnt fuel. I don't know those engines but from thinking what it needs to know to control fuelling -

 

MAF

intake temp sensor

boost sensor

fuel pressure (over pressure means it'll over fuel)

 

Plus of course injectors

 

But you've done half of those. Is there a way to reset the ECU? I wonder if it's still compensating for the issues you found?

[beko1987]

You get used to it. It's gr9 for sorting out tailgators

[Roostybroon]

Have you checked intercooler pipes for splits or slack clamps?

[Guest Hooli]

Oh that's a good point.

[dave21478]

A known problem on Freelanders with the same engine is dodgy wiring to the fuel rail pressure sensor. Dunno if that applies to the beemers though?

[Roostybroon]

Rover 75s have a daft o ring setup where the pipe connects to the intercooler. These leak for fun and cause the symptoms you describe. Do BM use the same thing on the 3 series?

[beko1987]

Judging by the amount of 320d's, 2.0tdi and 2.0tdci propelled cars I see chucking the clag out as the boot it up the hill of the m40 by stokenchurch every morning it's a common occurrence!

[Guest Hooli]

Oh just had a thought. Ever cleaned the intercooler out? They seem to fill up with oil & that'll make it smoke.

[They_all_do_that_sir]

Just thought that was a modern common rail diesel thing. Our 307 produces a respectable amount of clag if you boot it

 

Sent from my D6603 using Tapatalk

[tommotech]

Has the breather been changed that sits on top of the cam cover?

 

Should be replaced every third oil change.

[Bren]

Sounds like a breathing/induction problem.

 

Or just do what audi drivers do - ignore the mirrors.

[twosmoke300]

Split hose or egr stuck partially open

[twosmoke300]

Or injectors

[Tamworthbay]

I know next to nothing about diesels but could it just be an exhaust full of crap? And therefore in need of an Italian tune up? But as I said I know nothing about them so......

[Station]

I redlined this over the space of a few days (occasionally not permanently) and I can't see any smoke now - must've been clogged full of soot.

[sutty2006]

Plus one for split boost hose or similar