Technical Acrid white smoke from exhaust and rubber smell

[trekkingnut]

Was on my way to visit someone and got diverted with road closures everywhere and ended up going around little lanes in circles until eventually came back onto a main road whereupon I noticed plumes of white smoke coming out the back as I was driving along (engine was hot after the lane driving even though just pootling in 3rd gear ). I pulled over and smelt the exhaust which was acrid smelling but not oily (as in burning oil) or sweet (as in coolant) and the rear was not reall hot as would expect from a regen.

I drove back towards home as felt unnerved by it and had to go down a slow speed lane where I then heard a loud `1Dnk Dnk` noise and a burning rubber smell which made me think a pulley was seizing up though the aircon and alternator were working fine still but as I drove toward home, the smoke eventually cleared and it has been fine today so was it indeed a regen and the dnk dnk noise from hot exhaust and rubber smell from its mountings getting hot? - no warnings or lights and engine was running fine otherwise and could feel turbo kick in and normal `whistle` so not sure what happened if it was not a regen - any ideas out there as be grateful to know for sure if it was a dpf regen or something more worrying? - I have got millers additive in the tank at the moment (50ml on a full tank in case it is relevant.

thanks

 

[bugsymike]

Don't know the age etc. of your Doblo, but symptoms sound very like what I had in a 1.6 Citroen C3 Picasso when it was trying to do a Regen, pungent acrid white smoke etc.
If you have access to a good diagnostic tool it should tell you how long ago the last regen was and if it was successful etc.

 

[trekkingnut]

Hi, Its a 2006 so early DPF vehicle before it was mandatory (not sure if it is legal ir not to delete a DPF if fitted before 2009 or not as looking at massive money if DPF is on its way out?)

 

[bugsymike]

I think if the Vin. Number indicates it is fitted then you have to leave it on by law.
I have an 07 Skoda Scout with one, my daughter has a 09 VW Tiguan with with very similar engine and 4x4 running gear which does not and the details are in the service books that match the Vin. Numbers regarding that.
The C3 I mentioned I was able to take off and clean which lasted nearly 4 years with local use before needing to be replaced @ 223k miles and I was able to buy a good quality pattern DPF for just over £100, it was fairly easy job on that model.
For the moment if you have no warning lights or error codes I would suggest a decent run at dual carriageway speeds long enough for it to get the opportunity to run a Regen if it wants to, the problem comes with shorter journeys when it tries but cannot complete a Regen.
If possible to read the error codes stored it should tell you more about attempted Regens.
Your handbook or details online will advise the best conditions to do a regen , generally engine revs around 2500+ at a steady constant speed for a given time, but check as there may be specific advice.

 

[trekkingnut]

Thanks for reply - If the car had given me a warning about what it was doing I would have continued the journey rather than panic and go home!
I have deliberately not used the car on short runs which makes it even more annoying and there has been no loss of power. I was wary about aftermarket DPF`s hence the thoughts of deleting it (with reservations due to your valid points) Do the 1.9JTD 118BPH 8 valve engines have VVT by the way as unsure if they do or not? - might be the reason for the slight rattling when coming down from high revs. It was all going well until I put in the millers so maybe millers does something to make regen happen sooner rather than later?

 

[bugsymike]

Thanks for reply - If the car had given me a warning about what it was doing I would have continued the journey rather than panic and go home!
I have deliberately not used the car on short runs which makes it even more annoying and there has been no loss of power. I was wary about aftermarket DPF`s hence the thoughts of deleting it (with reservations due to your valid points) Do the 1.9JTD 118BPH 8 valve engines have VVT by the way as unsure if they do or not? - might be the reason for the slight rattling when coming down from high revs. It was all going well until I put in the millers so maybe millers does something to make regen happen sooner rather than later?

Unless others can advise better I would say no VVT on older 1.9 diesel Doblo.
Ideally read any error codes for more information.
Don't know about Millers, but an older 1868cc? non turbo 03 Doblo I had after fuel additive used air leak sucking air from fuel line at tank got worse, so maybe it "thinned " the diesel down to much as in less oily?