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Black smoke on acceleration

Black smoke is definitely passing the dpf. pressure readings? how can I find this out? I have a icarsoft MB v2 which I have updated but I still struggle to get it to do half the stuff its capable of
 
If you go onto view data under the engine ECU it should give you 'differential pressure'. Be interesting to see at 2.5-3k revs is the reading very low. Also look for regen frequency or distance since last regen.

What year and model is the Vito, I don't see it listed on earlier comments?
 
It's a 2011 mercedes viano 2.2.
Question though, should mercedes not have done this when they had it? They advised me to have the exhaust cleaned. Is this a thing? Do people clean exhausts? Clearly the cat/dpf are not doing their job if it's honking out this much black smoke. That's why I planned to take exhaust off clean it and maybe gut the cat and dpf before replacing but surely that would let more smoke out.
 
Is that EURO 4 or 5, if 4 it won't have a DPF?

Yes DPF cleaning is a common thing, can be done on or off the car.

To me it sounds like another issue that is causing the excess smoke and unburnt diesel. I would do a smoke test on the air side to check for split pipes or a cracked manifold and then move onto injector readings etc to check fuel readings.
 
I don't know if it's a euro 4 or 5. So I still think it's something causing it to run very rich. The intercooler pipes have been changed, the intercooler itself has been changed, it's been smoke tested by at least 2 places.
 
If you type your reg into totalcarcheck.co.uk it will show you what the Euro status is.
 
It's says 5a for euro thingy.
I don't know about boost reading. Is there anything that wouldn't show up on a smoke test until under turbo boost pressure?
 
The boost reading will tell you if the turbo is creating the correct pressure. If it was only making half the boost it would explain it however should log a fault and you would notice low power.
 
Update.
Black smoke sorted.... Now I have white smoke.
First how I fixed the black smoke- I removed the dpf, blocked all the holes and filled with a dpf cleaner and left it soaking over night. Then flushed it all out with lots of water, making sure to flush it back upstream rather than forcing particles through the meshing. I went to do the same with the cat however this was empty.
Took for a drive once all dried out and initially thought was great as zero black smoke.
Then I noticed when idle in traffic or on the drive a fair amount of white smoke comes out and doesn't seem to clear when warm either. Smells very fuelly too.
Local non merc garage have done a head gasket test and it's not a head gasket. Thinking it's likely to be low compression (yet to have compression test done). Is this likely and if so is it likely to be top end, valves ect or piston rings?
Did consider putting a can of the oil treatment ring seal stuff in.
It still drives and starts really well.
I do have a number of electrical anomalies like doors sometimes don't work until I disconnect battery and reconnect, recirculation button doesn't work and AC has a mind of it's own, but I assumed these are unlikely related to engine issues?

Thanks
 
Update.
Black smoke sorted.... Now I have white smoke.
First how I fixed the black smoke- I removed the dpf, blocked all the holes and filled with a dpf cleaner and left it soaking over night. Then flushed it all out with lots of water, making sure to flush it back upstream rather than forcing particles through the meshing. I went to do the same with the cat however this was empty.
Took for a drive once all dried out and initially thought was great as zero black smoke.
Good work.
Then I noticed when idle in traffic or on the drive a fair amount of white smoke comes out and doesn't seem to clear when warm either. Smells very fuelly too.
Identifying exactly what the 'white smoke' is will be key.
Local non merc garage have done a head gasket test and it's not a head gasket. Thinking it's likely to be low compression (yet to have compression test done).
For sure a HG can be half checked by looking for cross-contamination between oil and coolant but the integrity of the fire ring - where compression can be lost - can only be done by compression testing AFAIK.
Is this likely and if so is it likely to be top end, valves ect or piston rings?
HG - if low compression is the issue - is much more probable.
Did consider putting a can of the oil treatment ring seal stuff in.
It still drives and starts really well.
I do have a number of electrical anomalies like doors sometimes don't work until I disconnect battery and reconnect, recirculation button doesn't work and AC has a mind of it's own, but I assumed these are unlikely related to engine issues?

Thanks
Compression test and drilling down on whether the 'white smoke' is water based or fuel based (as you imply) would be my next steps.
 
How long have you driven it since? Are you sure it's not steam coming out after the dpf flush?
 
Slow update, and further problems. Ok so I don't think the garage I took the van to about the white smoke had a proper look at it if at all, the smoke is blue, if it wasn't then it certainly is now.
So it's definitely blowing blue smoke, and when sat idling it's quite a lot. The van gets used a lot and for long journeys. I'm starting to think all my issues with the black smoke were all linked to burning oil. It's done 230,000 miles ish so it's well used. I'm thinking it has has a oil leak possibly turbo seals or pcv stuff or something like that for a long time which clogs the dpf and only when you put your foot down does it have enough pressure to blow enough crap out. So after cleaning the dpf it allowed the blue oil burning smoke out a lot easier and noticeable.
It's had new boost pipes and intercooler so you'd like to think they would have noticed oil in the pipes if it was leaky turbo, but I don't have much confidence in this garage so maybe not.
Smelly very fumey in the engine bay also.
I'm not putting oil in so whatever it's burning isn't enough to be constantly topping it back up.
Also interestingly it was chucking out lots and lots of blue smoke at traffic lights, so much so I switched engine off as it was embarrassing, but no engine light. Then next time I drove it, hours later, the engine light was on but the blue smoke at idle was considerably less.
Still drives fine. Possibly a little more eager to change down a gear than I remember it used to be, but that might be just imagination.

Any suggestions would be great please.
 
Strange one. I think your comments re what appears to be oil burning as the root cause of the earlier issues is likely correct. Odd though that with copious blue smoke no oil is being consumed. My (petrol) smart with shot oil control rings was using considerable amounts of oil but never showed blue smoke - which I assume was the cat's work.
Given the above, possibly it is the PCV system at fault. I don't understand how it works on a diesel with EGR (which I suspect is capable of generating vacuum) so cannot advise but given the EGR system has the potential to pass oil vapours probably worthy of some investigation. Turbos have a certain amount of oil carry-over so maybe an increased amount in the intercooler went unnoticed due to that? I'd research diesel turbo sealing WRT to when (which driving condition) it is most likely to occur in and monitor accordingly. The physical check is for play of the rotating assembly - which requires considerable disassembly to access.
If none of the above and it is a hard parts problem, most likely oil control rings worn/seized but hard to diagnose definitively because the compression rings can be good and therefor show good compression when tested. That it cold starts and runs fine kinda implies the comp rings are OK. If it is oil control rings then oil enters the cylinder from below meaning there will be little sign of oil in the induction system, the reverse true for PCV/EGR/turbo compressor seal faults.
For oil to pass the oil control rings or compressor side of turbo requires vacuum - eg, some restriction in the induction system. What I mean is that a problem there could force rings/turbo to let oil past where otherwise they'd be fine. Not so the exhaust side of the turbo. If the problem is persistently at idle, I might consider disconnecting the turbo's oil feed (idle only!) and see if it stops the smoke. I'd check the return drain pipe for blockage before that though - in case it is creating excessively high pressure and forcing a leak.
Good luck!
 

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