E320 black smoke !!!!

[cliffym123]

has anyone any idea how i can cure a problem of excessive black smoke on my car .... while driving , it is fine , but when i approach a junction and have to throttle off , then when you accelerat again there is an almighty cloud of smoke out the back ... much to the dismay of following drivers!! .. i,ve added fuel injector cleaner , cleaned out the EGR valve , and also changed the EGR valve operating vacuum unit that is mounted on the nsf inner wing (plus a full service has just been done too) ... any suggestions would be greatly appreciated !!! please !!

 

[Mike J]

Smoke

Hi Cliff
You dont say but I am guesing its a diesel ???
Try the simple things first :-
(1) Use a good quality Fuel Shell etc
(2) Take it for motorway blast clear its lungs.
(3) Check the air filter sometimes a garage will just turn the old one over !!!
(4) and this is the limit of my Tech knowledge have the injecters checked.
Reading your message it seems your car is overfueling on the overrun which says to me the injectors are letting fuel passed.
Good luck
Mike

 

[mister_cee333]

Hi. I'm barking up the same tree as previous post here... years ago my dad had a Montego 2.0 turbo diesel but he drove long motorway miles at 65-70 mph. If he ever had to use heavy acceleration there was a cloud of black smoke from the exhaust. We tried injector cleaning etc etc but one day I decided to try the good old fashioned method. I took it out and held it at max revs in 3rd gear for a minute or so. Did this several times every 5 mins or so until exhaust was running clear. The difference was astounding...no black smoke at all under any load and better performance. It's worth a try mate - cheapest option first eh.
We also had merc trucks which were fitted with exhaust brakes. If this was used for the first time in a while it made the exhaust very smoky, but if you kept using it regularly it ran clear. My theory is that they clog up a bit if you don't clear 'em out once in a while.
Hope this helps.

 

[davebox]

On the mitsu pajero's this is common or so I am told.
The way a mate of mine clears them is to cool the vehicle for a while then face it uphill and wash the exhaust with small bursts from a hose (only short ones mind - takes the cr*p from them) Take it for a run with a good quality fuel cleaner ie forte or kudos. If you can use a hill to run the car up at high'ish revs this will help.
If it's still burning black after you have done this a few times then has to be overfueling, only thing is I do not know why it could be doing this (lots of electrical stuff that could go wrong).

 

[piestore]

320cdi smoke

HI

had a few of these the fix is to change the EGR valve as a complete unit