DPF regeneration

[pitpony]

Just had to have the car in the workshops to have the DPF regenerated which is not covered by warranty, the bloke who had the car before me did all the mileage just chugging around the lanes of Norfolk, my pont is any one ever used any of the DPF additives that you can put in the fuel , Happy New year to you all,

 

[WoodlandsCamper]

The Vauxhall Astra we had occasionally put up the DPF warning light when we had been driving around the town with no long distance journeys. The remedy to clean the filter was to continue driving up and down the local unrestricted dual carriageway until the warning light went out. Took about 6 miles to do the cleaning/regeneration.

 

[intransient1]

This is the curse of modern diesels.
Ford and Vauxhall seem to have the worst problems, my Kuga decided to go into limp mode while on a 4000 mile european holiday which happened the day after climbing up mountain passes at high revs for 30 plus miles so it should have burnt off any particles.
still a 10 mile run without the van in tow in fourth gear and 4000 rpm cleared it.
If you add in the EGR as well modern diesels should be cleaner, but now campaigners want us to change from diesel to petrol because of pollution especially in big cities where the most polluting vehicles are busses and taxi's as can be seen on Oxford Street in London which apparently is the most polluted street in the country.
Can't really see public transport changing to petrol engines.

 

[otherclive]

When we sold our caravan in March 2014 I was also glad to see the back of a 2010 XC70 D5. I never actually had problem with the DPF regenerating but did have sensor failure so drove over 100 miles on a dark winters night in limp mode. But the D5 with DPF uses extra fuel injected on the exhaust stroke to aid regeneration which had the problem of finding its way into the sump oil and leading to an increase in sump level. This was on a brand new car carefully run in, and not used on short hops. So Volvos answer was to issue a modification that recommended only filling the sump to half full, and then modifying the software such that the electronic oil level sensor would show the sump as full when it checked sump levels. Then if the sump level rose the system would alarm when it reached what was the original full level. Checking the oil level by hand was possible using technicians dipstick sited well down in the engine which couldn't be accessed until the engine was cool.So I wasn't happy about the possibility of running with the lub oil potentially diluted with dieso. Hence when the caravan went so did the Xc70 too. The replacement Subaru was chosen to be a petrol, non turbo and no touch screens anywhere, and with good reliability and safety too. But like all plans things change and we decided to buy another van last September, which is being changed tomorrow for something a bit more conventional. So I guess some ear defenders will be required as the 2.0 litre Boxer revs up. Perhaps a transplant from the WRX might help!!

Regarding the future of diesels for cars at the recent US 2017 car show the mainstream manufacturers all reckon that by 2025 the majority of their car output will be petrol and petrol-electric. Looking at what VAG are starting to put out then there should be no problems towing power-wise and torque-wise if the cars themselves are type approved for towing

 

[ProfJohnL]

My VW Passat 170 DSG has a DPF, and its a real pain. and its one major factor in my thinking about replacement cars.

Most of my journeys are less than 8 miles, a significant proportion are limited to 20 and 30mph zones, and the rest typically 50mph. The engine barely gets a chance to get to full working temperature, and as a consequence the car goes into a DPF regeneration cycle every couple of hundred miles.

This cycle is not displayed on the instrument, panel but is detectable by the engine refusing to change up until the revs exceed about 2250 rpm, and both on idle and when using the cruise control the engine has small surges which you feel. When this starts to happen, I try to do at least 20min run in 4th ot 5th with the engine revs between 4250 and 4500, which rather defeats the purpose of going to a diesel for fuel economy.

On a couple of occasions when I have been trapped on 30 mph roads and the regen has started, the DPF light has come on after a few miles, but Ive been able to clear it by deliberately doing a high speed run as above.

On one occasion and despite doing the normal regen the condition did deteriorate, and the car went into limp home. Even doing a sustained 40min run didn't clear it, and I had to go to a garage for them to reset the fault and get it out of limp home. It needed about an hours run to get it regenerated.

Its a problem that mars what in most other respects is a fine car. and its an issue that is colouring my thinking about my next possible car.

 

[pitpony]

The use of my Qashqai is very similar to the Prof with more often than not just going in to town till we start to go away with the caravan, after speaking to the service chap this morning he said it is a good thi9ng to add the DPF additive every two month but the additive I added this morning says every three thousand miles which in my case would be twice a year, so it is back on the bike for my trips in to town to the bookies,

 

[KeefySher]

An 'Itallian tune up' always works well, be it on a DPF or non diesel. If ever required, particularly for an MOT have always taken the car for a ITU on the nearby motorway, on at 1 junction, to next, turnaround and return at motorway speed and if necessary holding a lower gear. The old MH used to have no detectable emissions at MoT time after the ITU :evil: An ITU once a month is possible for most users, surely; and it must pay dividends over the long term.

If a vehicle is required for pootling round town is it to worth getting a small town car? We used to run a MH, a 4x4 and a large saloon car. We now have a large diesel tow car with a 3litre V6 that we use for the non town journeys, and a Fiat 500C for use as the town car. Small enough to park in any space, good gas mileage as the yanks say and only £30 VED to boot. Round here the Fiat 500 are very popular as 2nd cars. Ours is probably the best car we've ever owned, overall. For it's age it's in remarkable condition, fits us in, great in the sunshine with the roof down. OK it can't tow, but the S Klasse fulfils that role, and more.

 

[Keefanmaxx]

Like VW, my Antara has a DPF that self regenerates about every 500 miles. As for needing an 'italian tune up' .... no need as such but we do make sure it gets a decent run every few weeks.

 

[ProfJohnL]

... An ITU once a month is possible for most users, surely; and it must pay dividends over the long term...

I certainly can and do a fast run, but it always grates that such a process is necessary in addition to normal usage. I do think car manufacturers have deliberately played down the necessity and the impact of this necessary activity before a customer chooses a vehicle.

There is also another aspect of this which I have not been able to verify, but if the DPF is working, it collects the particulate matter. This is good as it has prevented it being discharged, but then during the regeneration,the stored particulate matter is effectively discharged into the atmosphere - just in a different place to where it was created!

 

[KeefySher]

Like VW, my Antara has a DPF that self regenerates about every 500 miles. As for needing an 'italian tune up' .... no need as such but we do make sure it gets a decent run every few weeks.

Is a decent run every few weeks not an itallian tune up?? :S

I recall on my first DPF car the manual said 20 miles at a constant 50mph once a month would suffice. I prefer 12 miles at motorway speed once a month!!! :evil: About 10 minutes and a third of a gallon of diesel once a month if required, which is not often in my case as I do sufficient mileage.

 

[pitpony]

Whoever decided that diesel cars would bring the world to an end and everyone would stop breathing if they ever drove through the West End of London so the way round it would be to have a filter box on the exhaust system called a DPF, what a good idea expensive to replace and expensive to regenerate in a workshop, in my case £245.00 with an oil change, when all this crap was being thought out by someone in RD on their computer programme, would it not go through their head that it would be good and cheaper for the motorist to have a system designed with a removable cartridge filter, just like when you go in for your service and have a new oil filter, fuel filter plus the air-con and pollen systems changed, anyone know a good vehicle with a decent petrol engine,

 

[KeefySher]

... An ITU once a month is possible for most users, surely; and it must pay dividends over the long term...

I certainly can and do a fast run, but it always grates that such a process is necessary in addition to normal usage. I do think car manufacturers have deliberately played down the necessity and the impact of this necessary activity before a customer chooses a vehicle.

There is also another aspect of this which I have not been able to verify, but if the DPF is working, it collects the particulate matter. This is good as it has prevented it being discharged, but then during the regeneration,the stored particulate matter is effectively discharged into the atmosphere - just in a different place to where it was created!

Yes but.. if governments had made different decisions to actually reduce emissions by lean burn for example in place of emission controls nearly 40 years ago, not incentivised diesel use through taxation regimes etc we would be in a different place. That's the problem with politicians making decisions :evil: :evil:

I recall driving big engined V6 & V8 petrol cars across the world that produced less power and torque but required the capacity to overcome the emissions controls therefore using more fuel to get the same output as a lean burn. :evil:

Then electric / hybrid vehicles currently being incentivised through taxation also discharges the creation of electricity in a different place to it's use. See what the politicians have done there?

A common theme arises :evil: :evil:

Bit like the non story re VW, it was always going to be a commercial result, initially £10bn was set aside, actual 'fine' £3bn. So despite protestations around the 'environment' it always comes down to cash money. Simples.

 

[Martin24]

Not all of us live near a handy local motorway and it is not necessarily possible for people with disabilities to make long journeys in the car as and when they feel like it. Not all families can necessarily afford a second car as a town run around so if you're in that situation it is probably just as well to forget the manual (who in life really has time to read it anyway) and just get on and drive the car as you want to or indeed need to.

 

[saint-spoon]

I am hoping that my twice monthly towing exercise, with a good 40 minute motorway run each way is enough to keep the engine clear

 

[ProfJohnL]

I do agree the political agenda's are often very narrow minded or even miss the nub of the matter, and sadly we will always suffer such issues as long as politicians who are rarely expert in matters they appointment themselves to deal with make the decisions. But then who is actually qualified to make such decisions?

Your point about electric vehicles simply shifting the emissions is true in part. The internal combustion engine even in it's most refined current form is still relatively in efficiently. And the fact it still burns fuel under compression is always going to produce more emissions than a burn under normal atmospheric pressure. The power generators do not haver the same space a cost limitations as the car industry, so they can and have done can lot of work to burn fossil fuels as cleanly as possible. Consequently the relative CO2 and other emissions from a power station are much lower than if the same fuel had been burnt in an car.

Also, the implementation of emmision capture is much easier at a single point source such as a power station than to attempt it on each individual car. So electric powered vehicles are much cleaner even when considering whole world issues.

 

[ProfJohnL]

Not all of us live near a handy local motorway and it is not necessarily possible for people with disabilities to make long journeys in the car as and when they feel like it. Not all families can necessarily afford a second car as a town run around so if you're in that situation it is probably just as well to forget the manual (who in life really has time to read it anyway) and just get on and drive the car as you want to or indeed need to.

I agree there are some people who do not have there same flexibility to do high speed regeneration runs. Which reinforces my point about the necessity of then not brought to the attention of potential buyers, especially those who may for any reason be unable to do them. This makes city bound drivers a less appropriate candidate for such cars, and that should be made clear by the sales people, as under the CRA the product must be fit for purpose.

The way most manufactures explain the DPF is to say it collects particles, and burns them off when running at high speed. Little mention of frequency of regeneration, or the fact sometimes you may need to do special trip to fulfill the process.

Ignoring the manual is not an option if the ECU detects an overburdened for, the car automatically Will drop into limp home mode, robbing the driver of the full performance of the vehicle, and often turning off other driving features like croiuse control.

If you have never experienced a turbo diesel dropping into limp home the sudden loss of power can be more than just inconvenient.

I was on a motorway slip road accelerating to match the speed of a gap in the traffic in lane one, and had started to move over when ding dong limp home engaged and it left me uncomfortably close to the following vehicle. I'll bet driver of the truck had few choice words about my driving.

 

[Raywood]

I do live near several motorways and the car does get at least one twenty mile run down one every month even when not using the caravan.
I did have a problem with the last car when the light started flashing. On that car a flash meant a problem rather than the need for a fast run which was the light staying on. I was confused as we had just towed from Chester up to Carlisle. I did book the car in when we got home and they said it was a faulty sender rather than an actual problem. What they did tell me though was that in these circumstances the coolant water can reach the sump so an Oil change would be needed and using it with the light on could cause further damage. I traded it in so do not know if any long term problems.
The hand book suggests a twenty mile run at 40 or more is needed to regenerate.
I do wonder however how people in remote areas where a twenty mile run at 40 may be difficult manage.

 

[Martin24]

Hi Prof,

I have to say yes we did suffer limp mode once in a previous car due to a sensor failing and it was no fun at all, especially with the van on the back.

Our current truck has done over three years with the odd long run with the van on. Most of the time it pootles about town and just the odd run now and again seems to be keeping her running just fine. It does have some sort of dpf display thing that I've seen when flicking through modes of the computer thing but no idea what it means.
Perhaps it's luck.

 

[pitpony]

Well you learn something new everyday, I never new that DPF additives are based on Cerium (really) and need the engine at 600 degrees to burn off the particles, but I have found a DPF additive that is based on Iron and can do the job when the engine is at at 350 degrees, 100,000 euros have been spent on it's development and it's German,

 

[otherclive]

Whoever decided that diesel cars would bring the world to an end and everyone would stop breathing if they ever drove through the West End of London so the way round it would be to have a filter box on the exhaust system called a DPF, what a good idea expensive to replace and expensive to regenerate in a workshop, in my case £245.00 with an oil change, when all this crap was being thought out by someone in RD on their computer programme, would it not go through their head that it would be good and cheaper for the motorist to have a system designed with a removable cartridge filter, just like when you go in for your service and have a new oil filter, fuel filter plus the air-con and pollen systems changed, anyone know a good vehicle with a decent petrol engine,

Theres plenty of good petrol cars out there but it all depends on what you want. BMW 3 and 3 series 3litres, Audis, Jaguars, Mercedes Kompressors, and the newer cars with smaller engines supplemented by a turbo. One of our best tow cars was the Saab 9000CSE 2.3 turbo, and later 9-5s have the same engine, but fuel costs with petrols will be higher than for diesels. We've just been down to Devon today to exchange our Trigano for a more conventional lump, very wet and not nice weather at all. Got 24mpg from the 2.0litre Subaru Forester which is comparable with our previous petrols and about 4mpg less than the D5 AWD XC70 did when towing. Must admit though that I do like a torquey motor and have a slight twinge of regret at not buying the Forester XT with 225bhp and oodles of torque, but the fuel costs and other costs ruled it out particularly as in March 2014 we decided no more caravanning for us!

 

[otherclive]

Not all of us live near a handy local motorway and it is not necessarily possible for people with disabilities to make long journeys in the car as and when they feel like it. Not all families can necessarily afford a second car as a town run around so if you're in that situation it is probably just as well to forget the manual (who in life really has time to read it anyway) and just get on and drive the car as you want to or indeed need to.

I agree there are some people who do not have there same flexibility to do high speed regeneration runs. Which reinforces my point about the necessity of then not brought to the attention of potential buyers, especially those who may for any reason be unable to do them. This makes city bound drivers a less appropriate candidate for such cars, and that should be made clear by the sales people, as under the CRA the product must be fit for purpose.

The way most manufactures explain the DPF is to say it collects particles, and burns them off when running at high speed. Little mention of frequency of regeneration, or the fact sometimes you may need to do special trip to fulfill the process.

Ignoring the manual is not an option if the ECU detects an overburdened for, the car automatically Will drop into limp home mode, robbing the driver of the full performance of the vehicle, and often turning off other driving features like croiuse control.

If you have never experienced a turbo diesel dropping into limp home the sudden loss of power can be more than just inconvenient.

I was on a motorway slip road accelerating to match the speed of a gap in the traffic in lane one, and had started to move over when ding dong limp home engaged and it left me uncomfortably close to the following vehicle. I'll bet driver of the truck had few choice words about my driving.

Some of the newer diesels have the DPF much nearer the exhaust outlet or virtually integrated in the manifold, and so will regenerate more easily in town stop/start conditions. Some Nissan/Renaults do, and the later Defenders did also as farmers often do very short journeys with little warm up time in cold conditions. The other aspect with the DPF is that even the best regeneration cycle will leave a fine ash residue that will eventually require replacement of the DPF.

 

[ProfJohnL]

...
I did have a problem with the last car when the light started flashing. On that car a flash meant a problem rather than the need for a fast run which was the light staying on. I was confused as we had just towed from Chester up to Carlisle. I did book the car in when we got home and they said it was a faulty sender rather than an actual problem. What they did tell me though was that in these circumstances the coolant water can reach the sump so an Oil change would be needed and using it with the light on could cause further damage. I traded it in so do not know if any long term problems.....

Very strange, What car was it? As I find it very difficult to see how coolant water would get to sump just because the exhaust is restricted by over burdened DPF. Sounds like some one was pulling wool over your eye's

 

[Woodentop]

The advice I was given by VW head office customer support is to drive for about 30 mins keeping the revs at 2000 or just over and that will do the regen. Alternatively 15 mins towing the caravan has the same effect.

 

[Keefanmaxx]

Like VW, my Antara has a DPF that self regenerates about every 500 miles. As for needing an 'italian tune up' .... no need as such but we do make sure it gets a decent run every few weeks.

Is a decent run every few weeks not an itallian tune up?? :S

I would say no as its a run at a constant speed in low gear rather than high speed.
We've not had a problem with the DPF, even since fitting a 'diesel chip' which effectively increases fuel pressure into the injector manifold to boost power and burn cleaner (according to the suppliers!)

When we were looki g for the previous car, the salesman did try to sell us a petrol engined model based on use and the DPF issue. We still brought the diesel and had no problems with it in the 3 years we had it.

 

[Gagakev]

Shogun manual states 40mph until the DPF light goes out!!! Does take about 15-20 mins

Ours always comes on a couple of days AFTER a long/towing run!!!!

Doesnt seem to come on when OH does her short journeys!!