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Discussion Starter · #1 ·
I have been warned about, and hence reading up on, these DPF's , or Diesel Particulate filters, which clean the exhaust gas of diesel engines, and are fitted by law.
I'm sure I'm covering old ground here, but can't find anything in the search facility, so appreciate any advice.

Apparently these devices are fine on cars that regularly do long journeys, but if used for mainly short journeys, or stop/start journeys, they don't get the chance to burn off the excess soot, can clog up, and be very expensive to replace.

Now of course this has not been mentioned to me by the dealership, so just wonder if anyone here knows more about it, or actually had problems with it, as apparently it would not be covered by warranty.

My problem is that I often work away, for lengthy periods, and then my wife would be using the car mainly for short journeys.
I've also heard that problems can be prevented by just giving the car a decent run along the motorway for half an hour or so.
(there goes the supposed fuel economy advantage of diesels ! )

Is this true, and if so, how often would you need to give the car a blast ?
 

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As you surmised, this has been discussed. I would suggest you have summarised the issue quite well. I would add that some vehicles seem to be more susceptible than others. As far as I am aware no one on this forum has reported a clogged DPF ............... yet.
 

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Friend of mine had this issue on a VW diesel car. He ran the car for a couple of years, commuting 40 miles each way on a motorway, and it was fine - and economical. He then relocated far closer to his office. Within 6 months, the economy of the car was shot, and so was the DPF - first a bunch of warnings, and then a bit of 'limp-home' mode, and ultimately a knackered filter and a huge bill.

He's now looking for a gas-guzzling petrol car as a replacement.
 

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Discussion Starter · #4 ·
All rather scary !
I'd like to read the previous discussions on the topic, but coming up blank when I search all forums for either 'Diesel particulate filter' or 'DPF'

Any suggestions how to find, or link ?

Thanks.
 

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The DPF was my biggest concern due to all the horror stories you read. My commute is just over 7 miles each way and my car will be a year old next month with just over 5,000 miles on the clock and so far no issues for me.

I have Ad Blue on my car which I understand helps the DPF burn off soot at a lower temperature. I keep a log of my regenerations and its seems to be roughly every 100 miles or so, but if I do longer journeys this distance obviously increases. The first sign I know its doing its thing is when idling in traffic the revs are higher and the Start Stop deactivates, also the car does feel different. It generally seems to do it on my journey home and usually does it in one go.

I do think it would be useful to have a DPF menu within the DIS that you could look at to see what stage the regeneration process is at as sometimes when I get home and the cooling fans are running I am never sure if its just cleared itself or its mid cycle or just about to start.

Hope this helps
 

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Friend of mine had this issue on a VW diesel car. He ran the car for a couple of years, commuting 40 miles each way on a motorway, and it was fine - and economical. He then relocated far closer to his office. Within 6 months, the economy of the car was shot, and so was the DPF - first a bunch of warnings, and then a bit of 'limp-home' mode, and ultimately a knackered filter and a huge bill.

He's now looking for a gas-guzzling petrol car as a replacement.
You have to heed the warning signs.

I do mostly short journey (under 6 miles), so as soon as I hear the fans going after I get out of the car, the next journey I take a short detour in dynamic, doesn't need to be fast as long as the engine is over 2k revs most of the time... 15-20 mins later all sorted...
 

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Discussion Starter · #9 ·
The DPF was my biggest concern due to all the horror stories you read. My commute is just over 7 miles each way and my car will be a year old next month with just over 5,000 miles on the clock and so far no issues for me.

I have Ad Blue on my car which I understand helps the DPF burn off soot at a lower temperature. I keep a log of my regenerations and its seems to be roughly every 100 miles or so, but if I do longer journeys this distance obviously increases. The first sign I know its doing its thing is when idling in traffic the revs are higher and the Start Stop deactivates, also the car does feel different. It generally seems to do it on my journey home and usually does it it one go.

I do think it would be useful to have a DPF menu within the DIS that you could look at to see what stage the regeneration process is at as sometimes when I get home and the cooling fans are running I am never sure if its just cleared itself or its mid cycle or just about to start.

Hope this helps
Yes,
Thanks, that does help.

It's just another thing I had no idea about, and no mention of it from Audi.
From reading the other 'Adblue' thread, it seems that it will be fitted to my 2.0 / 177PS S-line plus when it arrives in April.
But it s not fitted to the 3.0/ SQ5 models.

What's the reasoning behind that ?

Steppy, apart from your short daily commute, do you not take the car out for a decent long run here and there at weekends, as this is supposed to control the build up ??
Do Audi give any advice on this subject when you take delivery
 

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Steppy, apart from your short daily commute, do you not take the car out for a decent long run here and there at weekends, as this is supposed to control the build up ??
Do Audi give any advice on this subject when you take delivery
I travel to my parents every 4-6 weeks and that's 25 miles each way with a large chunk of that on the motorway, but I am a sedate driver and travelling at 70-75 and at that speed the revs are below 1500rpm

This past week I have had particularly bad nose to tail traffic and whilst stopped at a set of lights I knew the DPF was doing its thing so I went on the Motorway instead of my 30-40mph limit route home and put the gearbox into Sport mode, that kept the gearbox in 6[sup]th[/sup] instead of 7[sup]th[/sup] and at 70mph the revs were just over 2000rpm. I was only on the motorway for about 7 minutes, but when I came to a stop at the traffic lights on the slip road the Start Stop was working again so it obviously did its thing.

I wasn't given any advice on the DPF when I picked the car up, but I knew the car would have one as all diesel cars from a certain year (not sure of the date) have them. Speaking to the Master Tech when I was having some warranty work done he said DPF are much more sophisticated than there were and they are very efficient at doing what they do. If it doesn't do the regeneration in one go it will try it again the next time the car is driven and do this for 3 attempts. If it still doesn't do it then the light will come on and then you must take it for a motorway trip for 10-15 minutes with the revs over 2000rpm until the light extinguishes.
 

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If the fan runs on after the car is stopped what is that a sign of?

Getting both an SQ5 and a Golf GTD that won't do a lot of miles I am a bit concerned but in the event of a failure I will ask VW or Audi to show me the warning in the brochure or where the salesman highlighted this issue to me. Both cars are on low mileage PCPs therefore they are well aware of my expected usage.
 

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If the fan runs on after the car is stopped what is that a sign of?
That's what I am never sure of, but if the exhaust is clicking like made and the tailpipe is red hot when I get home then I take that as the DPF has just done its thing. All I know is that the next day it all seems to go back to normal

Sent from AutoGuide.com Free App
 

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It is merely a sign that engine needs cooling. Please note, it is not only cars with DPF where fan can run on after engine stops. You may notice a smell if the DPF regeneration was in progress when you stopped.

Good luck with a miss selling claim. I would suggest your chances of success are slim to none.
 

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This past week I have had particularly bad nose to tail traffic and whilst stopped at a set of lights I knew the DPF was doing its thing so I went on the Motorway instead of my 30-40mph limit route home and put the gearbox into Sport mode, that kept the gearbox in 6[sup]th[/sup] instead of 7[sup]th[/sup] and at 70mph the revs were just over 2000rpm. I was only on the motorway for about 7 minutes, but when I came to a stop at the traffic lights on the slip road the Start Stop was working again so it obviously did its thing.
Steppy, what do you mean the DPF was doing it's thing, burning off the excess? ?? and when you mention the start/stop feature working and not working, does the DPF control that automatically to help do that ?
Also, on another point, can the start/stop feature be de-activated manually anytime if driver doesn't want it ??
Thanks.
 

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Can't see why you assume that a claim would be unsuccessful, if a customer isn't warned at point of sale or in the operating manual I would assume there is a very strong case if handled properly.
 

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I've had the dpf regen light come on once in 20k miles, some of which are consecutive short journeys. The advise is to take it fir a bit of a blast or constant high revs for a number of miles and it will go off. I did as suggested, the light went off and regen completed. No issues to report since.
 
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