C270CDI blowing black smoke

[Dieselman]

Could this be realted some how?!

Maybe, just check no fresh air is being leaked away as that will be causing fuelling but no more air int ehcylinders.

It may just be that due to more air being forced into the cylinders the ECU is fuelling the engine more so shows more smoke as well.

 

[stasis]

Maybe, just check no fresh air is being leaked away as that will be causing fuelling but no more air int ehcylinders.

It may just be that due to more air being forced into the cylinders the ECU is fuelling the engine more so shows more smoke as well.

Fresh air leaking? From the head gasket? I dont think its leaking from the turbo manifols anymore. When i just got the car the engine bay is filthy and i foinf out that the gasket in the turbo manifol was leaking so i fixed that. Then the black smoke came.
Although it migh be a good idea to lay a "smoke screen" behind. LOL!!

 

[eurico]

Stasis
I had quite a lot of smoke puffing from my '02 C270 and cured it with a strong dose of injector cleaning fluid. It did wonders to the engine response also. However, there's still a short puff of black smoke when I floor it. This is normal as it's due to system injecting more fuel and later to light up the turbo for better engine response.

 

[1998K]

I've also noted that black smoke only if I hard floor.

Further, I had an irregular idle but only the very first minutes, I used an injector cleaning fluid and it went away but actually sometimes it's back,...I've never stopped the cleaning fluid (every fill up 50cc), any suggestion?

 

[eurico]

Marco, the irregular idle after startup is normal: the engine calculator is calibrating the injectors. You may notice that it raises and then lowers the idle speed and finally settles to the target value. If you only get black smoke for a very short while after flooring it, that's normal.

 

[stasis]

I've also noted that black smoke only if I hard floor.

Further, I had an irregular idle but only the very first minutes, I used an injector cleaning fluid and it went away but actually sometimes it's back,...I've never stopped the cleaning fluid (every fill up 50cc), any suggestion?

I have that too the idling is unstable. But after i changed the gasket in the turbo mnifold it stops doing that. Its not so erratic anymore.

 

[1998K]

Marco, the irregular idle after startup is normal: the engine calculator is calibrating the injectors. You may notice that it raises and then lowers the idle speed and finally settles to the target value. If you only get black smoke for a very short while after flooring it, that's normal.

thanks eurico for your confirmation it seems is perfectly as described by you: few minutes that raises and lowers the idle speed and finally settles to the target value

Marco

 

[1998K]

I have that too the idling is unstable. But after i changed the gasket in the turbo mnifold it stops doing that. Its not so erratic anymore.

out of the idle discussion, this remember that I've also changed the turbo inlet manifold (from air box to turbo) since there was a leakage (from the upper oil vapour pipes) due to a bad sealing. Dealer utilized a new and "improved" manifol (without a separate gasket like the old one) but the sealink was worst than before

I solved by myself with a specific hight temperature "red paste":bannana:


PS: DIY red paste a couple of Euro vs. brand new manifold much more expensive

 

[BarryS]

I hesitate to suggest it since I'm no expert, but when my 270CDi started smoking black smoke when accelerating it was simply the MAF sensor that had gone faulty, which does seem a fairly common occurance.

 

[eurico]

BarryS: I am having problems with my MAF sensor and it seems that these little buggers can do a lot o havoc with very unrelated items. I am compiling info and still doing some tests but will have breaking news soon.

 

[jadefox]

Sorry, being a muppet - posted in the wrong thread!

 

[Bertie]

My CLK 270 CDI Kicks out black smoke on accellerating too... ESPECIALLY after pootling around.. BUT I have fitted a chip a couple of months ago that i'm still experimenting with re fuel consumption... SO Far it seems to use more fuel [despite supplier's claims] and it appears to produce more black smoke too!! My previous car Alfa 2.4 multijet wasn't quite so bad but I haven't owned a diesel yet that didn't chuck out black smoke when booting it ...... I guess we just have to live with it?

 

[sweeper]

Black smoke is made worse by EGR which reduces combustion temperature, Euro 4 engines that use excess EGR to reduce NOx, (as oppossed to adblue injection) also has the underisrable effect of making excess black smoke and hence the use of particulate filters. lower power output, higher fuel consumption also a by product of emmission regulations, not to mention the energy used to make the filters and the extra energy required to burn off the hydrocarbons collected in the filter, reduced reliability etc. I have recently been working with an engine managment specialist from an engine manufacturer and they have calculated that overall emmissions from the latest euro 4 engines, taking everything into account are actually higher than that of euro 3 engines!! But going back to the black smoke issue, this is quite normal so long as performance and fuel consumption are acceptable and the vehicle passes the mot i wouldn't worry too much unless there is black smoke continuously.

 

[Dieselman]

Black smoke is made worse by EGR which reduces combustion temperature, Euro 4 engines that use excess EGR to reduce NOx, (as oppossed to adblue injection) also has the underisrable effect of making excess black smoke and hence the use of particulate filters.

they have calculated that overall emmissions from the latest euro 4 engines, taking everything into account are actually higher than that of euro 3 engines!!

Spot on and a poor attempt to control NOx.
My personal belief is that diesel emissions have been so low that the focus should be on efficiency only as this in turn reduces the overall output although NOx is increased at light running conditions.

All the current crop of add on controls do is to reduce one set of values at the expanse of another and fuel economy.