Diesel: Voluminous black smoke on acceleration?

[Paul S320CDi]

I have seen some diesel cars that pull away fast from traffic lights and they leave a cloud of black smoke/particles. Sometimes if the exhaust pipe is bent down, it leaves a black powdery patch on the road.

Is this just normal if you floor a diesel or is it a sign that something needs changing?

 

[twistedsanity]

black smoke is unburnt fuel, poorly designed or maintained engine

 

[petronious]

black smoke is unburnt fuel, poorly designed or maintained engine

Well I did not know that. Now I know, I thought it was just a diesel thing. Today has been another "school day" and have learnt something

 

[SLinKyjoe]

and "chipped" diesel engines throw smoke out like there is no tommorrow.

Due to the increase in fuelling form the re-map.

 

[Paul S320CDi]

Are there any circumstances when this is "normal"? (apart from chipped).

I thought I saw a glimpse of smoke out of my 320CDi but couldn't be sure if it was as bad as others cars I have seen.

 

[Bolide]

Black smoke = overfuelling

Typical on older turbo diesels on full throttle. Later cars should control the fuelling better and smoke less

Nick Froome
www.w124.co.uk

 

[Parrot of Doom]

It can be quite normal, my engine is well maintained and after a period of Daisylike driving, if I boot it I'll shove out a large cloud of black sooty crap.

 

[twistedsanity]

starting a turbo diesel from cold can produce black smoke, this is carbon that has formed from unburnt fuel as the turbocharger has cooled down after use, fire engines are a good example of overfueling, though not so much now with all the emissions regs, try you tube and put in "cummins diesel", many of the extremely quick diesel pickups belch out black smoke as the fuelling has been turned right up, although the properly tuned ones do not and are just as quick, i believe gale banks engineering are one of the companys who manage the same power without the overfueling

 

[NewMB]

and "chipped" diesel engines throw smoke out like there is no tommorrow.

Due to the increase in fuelling form the re-map.

Not so in my case. Engine chipped, wife have checked many times, no black smoke while driving nor on start-up.

 

[David Nock]

Didn't I read on a post somewhere that the latest eurocap diesels throw black smoke on occasions when doing an auto clean of their particulate filter?

 

[NewMB]

Didn't I read on a post somewhere that the latest eurocap diesels throw black smoke on occasions when doing an auto clean of their particulate filter?

Hm..... I have read something along those lines in Auto Express as well.

 

[Paul S320CDi]

What does the little knob and the dial mean on the air filter box? Is it supposed to tell you how much life is left before the filter needs replacing? Mine is showing all red and the filter does look black on the intake side.

ASSYST is saying 3000miles to Service A still.

I wonder if it's worth me changing the filter now anyway. I've only just got the car and it's always an unknown about the serving. The book has been stamped regularly, but it's not until you do it yourself that you can be sure it's done on time.

Would a bottle of diesel injector cleaner be of any use.

I've only had the car four days and looking out the rear window during acceleration is not something I've done before, but I noticed today that if I accelerate from a standstill and feel the turbo working it is always accompanied by sooty exhaust. Accelerating to overtake doesn't seem to emit soot, or at least not enough for me to see.