Clouds of smoke from exhaust

[R W]

This morning traveling to work, leaving the town all was normal, drove 10kms to the first village & under the street lights I could see clouds of white smoke behind the car. I immediately checked temp, pulled in & stopped the engine. The smoke immediately stopped so it was coming from the exhaust & not something else burning. The smoke had a toxic / acidic smell & definitely not oil or fuel smell. I found nothing wrong, then restarted the engine & all was well again, running perfect & not a trace of any smoke.

The car is a V6 E320cdi fitted with a DPF. Is this smoke a normal process of a DPF cleaning process, as I can’t find any other reason for the smoke. Any advice or ideas would be appreciated.

 

[oigle]

This morning traveling to work, leaving the town all was normal, drove 10kms to the first village & under the street lights I could see clouds of white smoke behind the car. I immediately checked temp, pulled in & stopped the engine. The smoke immediately stopped so it was coming from the exhaust & not something else burning. The smoke had a toxic / acidic smell & definitely not oil or fuel smell. I found nothing wrong, then restarted the engine & all was well again, running perfect & not a trace of any smoke.

The car is a V6 E320cdi fitted with a DPF. Is this smoke a normal process of a DPF cleaning process, as I can’t find any other reason for the smoke. Any advice or ideas would be appreciated.

Sure sounds like DPF issue. Normal. Really environmental things aren't they....

 

[R W]

Oigle.
Thanks for your reply & reassurance that its “normal” I hope your right. The car traveled back home & to work again this morning faultlessly a distance of 90kms. The only thing I have done, recently was to add a bottle of Forty injector cleaner to the tank last week. Plus due to weather conditions here I have just been leisurely plodding along,& from what I read DPF systems don’t like leisurely driving. Do you know if the Forty additive plus the fact it has been leisurely driven would have this effect on a DPF system. I am not very knowledgeable about cars with DPFs so any advice would be welcome.

 

[oigle]

Oigle.
Thanks for your reply & reassurance that its “normal” I hope your right. The car traveled back home & to work again this morning faultlessly a distance of 90kms. The only thing I have done, recently was to add a bottle of Forty injector cleaner to the tank last week. Plus due to weather conditions here I have just been leisurely plodding along,& from what I read DPF systems don’t like leisurely driving. Do you know if the Forty additive plus the fact it has been leisurely driven would have this effect on a DPF system. I am not very knowledgeable about cars with DPFs so any advice would be welcome.

I too have little experience with DPF's. My ML is not so equipped and for that I am thankful. MY comments were based on knowledge I have gained from this forum when more knowledgeable people have talked about DPF issues.
It seems that it is important to give the car a longish run with a bit of welly every so often. If you don't the system can and will block up and fail. Then you need a new DPF and that is money!!! Forte additives would make little or no difference and, in my humble opinion, are of no real benefit. Of course, with all such products, there are people who will swear by it.

 

[R W]

oigle.
I agree with your comments about additives, I have never found any real benifit using them. The reason I bought the Forty additive was my fuel guage was reading incorrect & some people advised a cleaner may clean the contacts of the sender units so I thought I would give it a try. As it turned out the fuel guage started working correctly but I added the Forty anyway since I had bought it.
I will try to give the car some "welly every so often" but the roads here are treacherous, compacted ice & most nights -20degC with virtually no grit or salt laid. That is why I have been driving it “leisurely”.
A normal journey to work is 45kms & I try to keep to 60kms per hr if possible during this bad weather, is this too slow to keep a DPF clean?.
If this driving style will cause damage to the DPF, I can use my E290 during the bad weather .
Thanks again for your advice

 

[oigle]

You probably need more professional advice here than I can give you. I would imagine that you may encounter some problems driving in that manner. The very cold conditions are probably going to impact it too as I think the DPF needs to get to a working temp to do its periodic cleanout.
I believe there is a service that a dealer or indie can do in the workshop every so often to clean it out if the driving conditions dictate. Maybe you should send a PM to one of our indies, or make a phone call, if they continue to ignore this thread. If you have a local reputable dealer or indi, maybe a phone call would be good.

Glad I don't have to suffer your weather

Ian.

 

[R W]

Iain.
I am working in Bishkek, Kyrgyzstan where I have this car, there are no Indy’s to speak of & the so called MB garages have no experience of the V6CDI or DPFs. That was one of my reservations about buying a complex car, but I like the 320cdi so much I thought I would take a chance on one being OK.
I can ask a local indy in UK as I am quite friendly with him but I am not due to go back for 6 or 7 weeks yet but could try to phone him. I may try for some answers on the other side, if there is no replies from them, I will keep my fingers crossed it continues to run OK till I return to UK & get some advice there.
So far its been faultless again, running perfect & no smoke.
Thanks for your advice & taking the time to reply.

 

[oigle]

Now I understand where the temperatures come from. Thought they were a bit low for merry England.....
I'll see if I can dredge up a reply for you from one of the indi's. No promises!!

 

[R W]

Ok thanks Ian, it would put my mind at rest & stop me worrying for the next 6 weeks.
Thanks for your help.

 

[thebandit]

Not 100% on this but don't DPF re-gens normally take place during a high speed run, say averaging 55+mph ?? Was this speed typical of your first 10kms ?

If not it could be something more sinister especially since it corrected itself after switching off and restarting.

 

[R W]

Yes I suppose it was typical, I drove approx 4kms stop start out of the town, then its about 15kms to the first village ( where I noticed the smoke). Weather was reasonable & the speed limit is 90kms(56mph) so I would be doing 90kms for the 15kms( 10 miles).

 

[RobWheatley]

Certainly on my old Citroen with a DPF that would re-generate only if the speed was over 50mph (i think) it depended on how it was driven too, cars with DPF's do not like town/slow driving so the old Italian Tune-up method worked if it had done a lot of slow journeys. I could force a re-generation cycle by holding a lower gear to get the revs up as it was triggered by engine speed not road speed.
I have the Citroen Lexia diagnostics stuff and could check how long between re-generation cycles, used to be about every 400-450 miles.

 

[Steve@Avantgarde]

The DPFs will only regenerate at a certain rev range at a certain temperature and under specific driving conditions such as motorway driving. I cannot see how a faulty DPF will cause it to smoke so much without there being some other circumstances and this is where speculation will creep in.

A failing injector dumping fuel could overfuel and cause a high ash content in the DPF causing it to regenerate even a failed EGR valve can cause serious running and smoking issues.

I had a sprinter here back last summer with the Euro 5 emmisions package which was smoking badly and going into limp mode. 2 injectors were dumping fuel which bunged the DPF so badly it couldnt regenerate quick enough which in turn knackered the EGR valve. It to have all 3 components.

There must be some fault codes to go on with this fault or at least some live data to look at.

 

[R W]

Steve.
I could have the car booked in to read the fault codes, but would probably be next week before I could have it done & tell you the codes.

When these DPFs regenerate do they produce smoke at all,& if so is it a toxic smell, like what I had?.

On Monday morning when the smoke occurred it was like a smoke screen behind the car, could not see exact colour but looked white under the street lights. I stopped it as soon as I saw the smoke which had a very toxic smell to it, not like an oil or fuel smoke. Checked coolant , oil & everything seemed OK, I restarted it & no smoke, drove it to work running perfect. Its now done almost 350kms since the smoke episode & no hint of smoke.

Today I ran it back from work keeping the revs up around the 3k mark by running in the lower gears & tried to give it some work to do, accelerating up to higher speeds. It ran perfect, cannot fault it.

I don’t know if its recent history has any bearing on the smoke issue but. I bought the car from Germany, in September, it took 8weeks to get here by train so for at least 3 months it has just stood doing nothing. Since it got here it has covered approx 1000kms, but no real blasting speeds, its just been leisurely driven due to the road conditions & weather.
I will check tomorrow when they can read the codes for me.

 

[R W]

Steve, or anyone who can explain the fault codes.
Finally got the car onto star today, had two fault codes logged but none active.
Due to being in Russian my translation is limited but

Fault code # 2043-002 was logged as B6/1 ( I think camshaft position sensor,)incorrect
Fault code # 2616-002. Pressure sensor B60 giving incorrect data

They cancelled the fault codes as they were not active & I will return in a week or two to check if they or any faults have re-appeared.
Car is continuing to run perfectly with no hint of any problem or smoke.