I have a 2011 R300 CDi. Recently when I put accelerator all the way to the bottom, the car will have a lot of black smoke. Funny is the smoke only come once. And need to wait for around half hour. And I put accelerator all the way, black smoke comes again, but this time, will have less...
I told dealer, they said it was because the air filter was block, and replaced a new one. But still the same!!
Do anyone know what happen?

Kevin

Hello Kevin,

You do not say where you come from as countries have different environmental pollution rules. Do you have a DPF?.

My 2007/2008 220CDI creates black smoke on hard acceleration especially from low revs when the turbo charger is caught out & has to spin up to supply the correct fuel air ratio.I do not have a Diesel Particulate Filter . Engines with DPF's fitted would release less/no carbon under heavy acceleration.

My previous car, a 1994 Peugeot diesel would completely black out the road if the turbo was caught out.

So if you do not have a DPF I would say that it is normal but not the way to drive on a regular basis.

John.

If it doesn't smoke again for at least 30mins then it's just loose soot in the exhaust system being blown out under hard acceleration. Unless it's smoking consistantly then I wouldn't worry about it. Sounds like your car doesn't have a particulate filter.

Do the filter come standard? Can I refit one? I have a 2006 ML320CDi, never have black smoke.(Of course, it has a lot other problem)

Kevin

Particulate filters are not fitted to all diesels in all countries. Depends on the regulations.

If you do not have one think yourself lucky because of the possibility of it blocking at some stage . It also has a regenerative process which is complicated when only short trips are made ie not enough heat produced in the exhaust to burn off the carbon.

Drive conservatively & you will have no smoke ....easy ....

I wouldn't worry about it, it's normal. It's just loose soot being blown out of the exhaust, if it doesn't smoke again for 30mins that shows it's not the engine creating the smoke at that moment, it's just blowing out a buildup over the last 30 mins.

Black smoke is a good thing with diesels. White smoke is what you need to worry about.

I have only seen black smoke one time, when I test drove my car.

I think it had sat for a long while, and it wasn't warm at all when I put it on an entrance ramp and stomped on the pedal.

In 25,000 miles, I've never seen it again.