2001 220 cdi periodically blows grey/black smoke and has rough idle.

[Moumik]

Hi. I am new to this group and I have tried to search for this problem but can't find a specific thread with the exact problem that I have.
Therefore I will ask again.

I have a 2001 220 cdi w203
Sometimes it goes into a very rough idle and blows grey or blackish smoke. But if I step the accelerator pedal to the floor it almost every time goes back to normal state.
A friend of mine has a professional tester and the only issue that could be engine related was some strange values from the EGR.
It is a bit dirty. So I cleaned it with some EGR cleaner. Right after that it was running better than ever. But this morning it had a "incident" again.
I am thinking about injectors or a air leakage?
The EGR alone could not cause this problem?

Does someone have a answer to this problem or had similar experiences?

 

[mioba]

could be many things. PCV, turbo, turbo actuators, filters, leaks of pipes.

Needs the codes read and live data analaysed.

Where are you located. someone may have a pointer for a good garage.

Throwing parts at a car (injectors, pipe work) just gets unnecessarily expensive.

 

[Moumik]

could be many things. PCV, turbo, turbo actuators, filters, leaks of pipes.

Needs the codes read and live data analaysed.

Where are you located. someone may have a pointer for a good garage.

Throwing parts at a car (injectors, pipe work) just gets unnecessarily expensive.

I was hoping for a simple answer.
But I guess that I will have to test it again and write down the codes.

I am from the Faroe Islands. There is only one official Mercedes Benz dealer in the country.
But most workshops should be able to test most common codes.
My friends tester can read most of them. Only some of the MB specific service menus where not available.