smokin !

[chris810]

Whilst sorting the mechanical issues on my newlely acquired car out, I have come across one which I have no experience of so I thought I would ask the collective 😀

My car smokes, it exhausts black smoke on tickover , it smokes quite a lot whilst driving, and on hard acceleration leaves a large ball of black smoke in the road for the following driver to pass through. Now I have noticed that cars are not tailgating me so I would assume the smoke is a bit extreme.

I have been advised to remove all the injectors and get them tested and adjusted, I have been advised to replace the MAF sensor as a first move, then decide what to do, I have been advised that the car may have a performance map on it which is causing my issue.

I don't know which is the most prudent course of action and I could do with some sensible advise.

[Deanhempshall]

Blocked Egr valve could be aiding to the smoke?

[Shadeyman]

Originally Posted by Deanhempshall

Blocked Egr valve could be aiding to the smoke?

...

[chris810]

Thanks guys having read a few threads that sounds like a diy issue however, as people block off the EGR valve with no ill effects how does a blocked one produce vast amounts of black smoke ?

[Deanhempshall]

Originally Posted by chris810

Thanks guys having read a few threads that sounds like a diy issue however, as people block off the EGR valve with no ill effects how does a blocked one produce vast amounts of black smoke ?

Not opening enough causes a considerable amount of coking up of the EGR valve. Blanking them off means exhausted gases can't be recirculated around the engine.

[Tannaton]

Black smoke is usually excess diesel... white or blue smoke would be oil or un-burnt diesel. It sounds like for some reason you have one injector delivering too much fuel to one cylinder - suggest you try and disconnect each injector in turn and see if this reduces the smoke. Note - this will put the engine light on and log an injector open circuit error so don't do this unless you have VIDA or other OBD reader that can clear codes.

As it's a new car to you - consider treating it to a couple of tins of Liqui Moly Diesel Purge - lots has been written about it on here. Cheap and usually results in noticeable improvements.

[chris810]

Thanks for that
The only time I have seen smoke like it was when I had a blown intercooler on my xc70, I think it's definately overfueling, I have been told that the over correction figures are all over the place, what does that mean?
Worn or duff injectors and the computer trying to make sense of it ?

[cheshired5]

+1 for Diesel Purge.
Also, because you're running your engine on it, the exhaust gasses will be infused with it so will give the EGR a little work over too.
I don't know whether your mileage is high like mine but I have nothing in my EGR and it isn't blanked.

[ianu]

What age & mileage ?
Possible intercooler leaking. Look for oily mist around the front rad top and bottom. Are you getting hesitation on acceleration?

[chris810]

The milage is shown as 130 k but that might not be true, I have no hesitation on acceleration it goes smoothly ( but not that quickly, last car was a 3.5 ltd v6 petrol) I don't see any oily misting.

So do I get the injectors checked ? Knowing that it is only one part of a process or get a base Map back on the car so I know I am working from standard?

To my mind if it is a mapping issue then no matter what the injectors are like then I can never get it right, but if the injectors are worn then the mapping will not be helping matters, but at least I can get a compression test done while the injectors are out.

If it's an intervoler then it's all buggered and won't get cured with the above work

😡