Mrs J now has an Android 'phone, so I've downloaded the VAG DPF app. After a 95 mile journey at legal speeds yesterday, these are the key values: soot mass 14.37g, 141 miles and 279 minutes since last regen, oil ash residue 5.9g, soot mass measured 0.48g. I've only just found out about the bar display showing % full, so I didn't note the % value. I understand that passive regeneration occurs during a run, so does this remove significant amounts of soot? Which value indicates the condition of the DPF and at what level is it 'full'? As we cover a relatively low mileage for a diesel I'm keen to know that I'm doing enough longer runs to keep the DPF in good order. Thank you in advance for your help. Jimmy
Jimmy
oil ash residue is what left in the DPF
don't know what the full figure is mine displays in litres.
Passive regens happen for me on long journeys when the engine is working hard, doesn't seem to remove much but I've not checked soot figures closely whilst driving.....
When the graph reaches 100% it will do a full regen.
don't know what the full figure is mine displays in litres.
Passive regens happen for me on long journeys when the engine is working hard, doesn't seem to remove much but I've not checked soot figures closely whilst driving.....
When the graph reaches 100% it will do a full regen.
That's helpful and thanks Idleness. When we next go out on a long journey, I'll ask Mrs Jimmy to drive and I'll watch the app.
Hi Ken. I bought an onboard diagnostics scanner, OBD2, which plugs into the diagnostics socket under the dash on the driver's side just above the right knee. Mine cost £13.29 from Amazon. It communicates with the Android phone app via wi-fi. The VAG DPF app cost £3.30. It isn't available for the iPad, although there are other iPad apps which can carry out all sorts of clever stuff, including cancelling error codes etc. I'm only interested in the DPF condition, hence the VAG app.
I finally got my ELM327 diagnostic port plugged in about 3 months ago and communicating with the Android VAG DPF app via Bluetooth. Since then I’ve been gradually building up a sense of values and what is really happening. Usually when Wilma is driving, but on occasions with the phone wedged firmly between the dials, masking the Maxidot display.
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Rest of above post after needing to change devices:
The difference between calculated soot mass and the measured soot mass is interesting. measured always seems lower in my case.
The app settings also include a section on how frequently the readings update. Longer intervals help save battery power if not running on charger. Can't recall what the other worthwhile settings are called exactly. But the option that switches on the rate of soot deposition (in purple at top right corner) is one of the most useful. As is the active display that shows green arrows in the DPF symbol at upper centre.
Normally the DPF symbol is grey (with the green arrows if you have the active display setting on), but during a regen turns bright red (like the DPF itself, if you could see it?).
Highest Calculated Soot Mass I've seen is in the 30s (g) but may depend what units you have selected in Settings. Reducing to low single figures after a regen.
The rate of soot lay down is fascinating. As you would expect when accelerating hard, that rate goes up. I've seen the high 50s mg/mi. I had expected a long motorway drive would achieve more passive soot burn. But that only seems to happen when the revs are prolonged and steady between 2500 and 3000 rpm, but more crucially when the exhaust gas / DPF input temperature exceeds 250-300 degrees. But the engine has to be working that bit harder, like a long uphill stretch for that to happen. Then the rate of soot deposition goes negative. As it burns off soot, but only at a rate similar to the range of deposition rate values.
On our car (8 years and 200,000 miles old on its original DPF), when the % full gets into the 75-80% range, then an active regen gets triggered. Even on a long motorway run, slightly to my surprise. Then the post-combustion fuel injects kicks in (the three readings at the base of the display), as the ECU injects extra fuel during the exhaust stroke to increase that crucial exhaust temperature. The exhaust gas temperature shoots over 600 degrees at DPF input and the soot deposition rate goes into high negatives, -1000 to -1250 g/mi having been seen at 50mph on a long run with the engine around 2500rpm. Till the %full drops back to single figures after a few minutes and everything goes back to "normal".
Overall conclusions so far:
- slightly surprised how ineffective running for long periods and medium to higher revs is at reducing soot mass. Some reduction, but nowhere near as much as during a proper regen when post-combustion injection is raising gas temperature. More like little or no soot deposition in those conditions.
- those DPF temperatures really do get seriously hot!
- Those proper regens are really very effective, provided not interrupted.
- I seem to be getting those regens, of which I was previously unaware, between 250 and 400 miles of driving, depending on journey patterns. At least one per tankful of fuel. Sometimes two if a lot of short journeys and cold starts.
Still a little early to reach any other conclusions. But quite enlightening so far.
The difference between calculated soot mass and the measured soot mass is interesting. measured always seems lower in my case.
The app settings also include a section on how frequently the readings update. Longer intervals help save battery power if not running on charger. Can't recall what the other worthwhile settings are called exactly. But the option that switches on the rate of soot deposition (in purple at top right corner) is one of the most useful. As is the active display that shows green arrows in the DPF symbol at upper centre.
Normally the DPF symbol is grey (with the green arrows if you have the active display setting on), but during a regen turns bright red (like the DPF itself, if you could see it?).
Highest Calculated Soot Mass I've seen is in the 30s (g) but may depend what units you have selected in Settings. Reducing to low single figures after a regen.
The rate of soot lay down is fascinating. As you would expect when accelerating hard, that rate goes up. I've seen the high 50s mg/mi. I had expected a long motorway drive would achieve more passive soot burn. But that only seems to happen when the revs are prolonged and steady between 2500 and 3000 rpm, but more crucially when the exhaust gas / DPF input temperature exceeds 250-300 degrees. But the engine has to be working that bit harder, like a long uphill stretch for that to happen. Then the rate of soot deposition goes negative. As it burns off soot, but only at a rate similar to the range of deposition rate values.
On our car (8 years and 200,000 miles old on its original DPF), when the % full gets into the 75-80% range, then an active regen gets triggered. Even on a long motorway run, slightly to my surprise. Then the post-combustion fuel injects kicks in (the three readings at the base of the display), as the ECU injects extra fuel during the exhaust stroke to increase that crucial exhaust temperature. The exhaust gas temperature shoots over 600 degrees at DPF input and the soot deposition rate goes into high negatives, -1000 to -1250 g/mi having been seen at 50mph on a long run with the engine around 2500rpm. Till the %full drops back to single figures after a few minutes and everything goes back to "normal".
Overall conclusions so far:
- slightly surprised how ineffective running for long periods and medium to higher revs is at reducing soot mass. Some reduction, but nowhere near as much as during a proper regen when post-combustion injection is raising gas temperature. More like little or no soot deposition in those conditions.
- those DPF temperatures really do get seriously hot!
- Those proper regens are really very effective, provided not interrupted.
- I seem to be getting those regens, of which I was previously unaware, between 250 and 400 miles of driving, depending on journey patterns. At least one per tankful of fuel. Sometimes two if a lot of short journeys and cold starts.
Still a little early to reach any other conclusions. But quite enlightening so far.
Thanks Flintstone for such a detailed description. You have pointed out features I wasn’t aware of so on the next drive I will watch the display closely.
Question not stupid at all. :smile: took me a while to figure out what was going on properly. As distinct from what I had imagined was happening before I got the app display working with the Extra Data ON. Even now, I’m not sure if I’m reading everything correctly. But if two of us are interpreting the same way, that’s a good start.
When I’ve got a chunk more running and values in my head under normal running conditions, I may try seeing if there is a detectable difference in any of the figures reached, when there is a dose of Archoil 6400 D-max in the fuel. But that may be a couple of months yet. And dependent on me getting my hands on the Yeti for long enough at a stretch. As I had last week.
Now wishing I had a similar app for the BMW. :sad:
When I’ve got a chunk more running and values in my head under normal running conditions, I may try seeing if there is a detectable difference in any of the figures reached, when there is a dose of Archoil 6400 D-max in the fuel. But that may be a couple of months yet. And dependent on me getting my hands on the Yeti for long enough at a stretch. As I had last week.
Now wishing I had a similar app for the BMW. :sad:
Just lifted this from another site
VAG DISESEL PARTICULATE FILTERS
Courtesy of David Bodily Volkswagen Technical Support Specialist
Diesel Particulate Filter (DPF)
Detailed below is important information outlining the function and features of the Diesel Particulate filter which all members of your team need to be aware of.
Diesel particulate filters are becoming more commonplace on diesel engines, particularly sizes 2.0L upwards. This is in order to reduce the exhaust emissions as required by European legislation.
The prime reason for a DPF is to reduce particulate matter entering the atmosphere. Particulate matter is found in the form of soot, which is produced during diesel combustion. The DPF traps most of the soot which would normally travel down the exhaust and into the atmosphere. The DPF can hold a certain amount of soot, but not a huge quantity and therefore it needs to go through a process called ‘regeneration’ in order to clear the soot loading. When the soot goes through a ‘regeneration’ process it will be converted to a much smaller amount of ash. The ash is non-removable. There are two types of ‘regeneration’, passive and active.
During long motorway journeys, passive regeneration will occur. This needs no intervention from the engine control unit. Due to the raised exhaust temperatures on a long journey (temperatures between 350 and 500°C), the procedure occurs slowly and continuously across the catalytic-coated (with platinum) DPF. The catalytic-coated DPF is situated close to the Engine, therefore the exhaust gas temperature is high enough (500°C) to ignite the soot particles. Due to this soot is burned-off and is converted into a smaller amount of ash.
Active ‘regeneration’ is when the ECU intervenes when the soot loading in the DPF is calculated to be 45%. The procedure lasts for about 5 – 10 minutes. Specific measures are taken by the ECU to raise the engine exhaust temperature to above 600°C, these include switching off the exhaust gas recirculation and increasing the fuel injection period to include a small injection after the main injection. The soot particles are oxidised at this temperature.
The ECU will trigger a regeneration process, if for some reason this is aborted, ie. customer slows down, stops etc, the process will be resumed when regeneration conditions are once again met, above 60km/h (38mph). This will continue for 15 minutes.
If after 2 attempts of 15 minutes, a successful regeneration has not been possible, the loading will increase. At 50% soot loading, the ECU will continue to maintain maximum exhaust temperatures of 600°C to 650°C to cause a regeneration process. The system will try to run a regeneration process for 15 minutes. If unsuccessful, the system will repeat this process for a further 15 minutes, if still unsuccessful, the DPF light on the driver display panel will then be lit.
The owners handbook states, the DPF symbol lights up to indicate that the diesel particulate filter has become obstructed with soot due to frequent short trips. When the warning lamp comes on, the driver should drive at a constant speed of at least 60 km/h for about 10 minutes. As a result of the increase in temperature the soot in the filter will be burned off. If the DPF symbol does not go out, the driver should contact an authorised Volkswagen repairer and have the fault rectified.
At 55% soot loading the DPF light is lit on driver display panel. At this point the customer should follow the advice in the handbook. If they ignore this information and continue driving the vehicle until the soot loading reaches 75% without successful regeneration, additional warning lamps will light up. At this point the customer will also be complaining of lack of power, etc.
At 75%, regeneration is still possible with the use of the VAS tester. Only when the loading is above 95%, is it necessary to replace the DPF unit.
Operating Status System Response
45% DPF Load Level 1
Normal Regeneration
50% DPF Load Level 2
Regeneration at maximum exhaust temperatures
55% DPF Load DPF lamp
Regeneration from 60 km/h onwards
("See operating manual")
75% DPF Load DPF, SYS and MI lamp
Torque limitation, EGR deactivation,
Regeneration via VAG tester only
95% DPF Load Replace the DPF Unit
VAG DISESEL PARTICULATE FILTERS
Courtesy of David Bodily Volkswagen Technical Support Specialist
Diesel Particulate Filter (DPF)
Detailed below is important information outlining the function and features of the Diesel Particulate filter which all members of your team need to be aware of.
Diesel particulate filters are becoming more commonplace on diesel engines, particularly sizes 2.0L upwards. This is in order to reduce the exhaust emissions as required by European legislation.
The prime reason for a DPF is to reduce particulate matter entering the atmosphere. Particulate matter is found in the form of soot, which is produced during diesel combustion. The DPF traps most of the soot which would normally travel down the exhaust and into the atmosphere. The DPF can hold a certain amount of soot, but not a huge quantity and therefore it needs to go through a process called ‘regeneration’ in order to clear the soot loading. When the soot goes through a ‘regeneration’ process it will be converted to a much smaller amount of ash. The ash is non-removable. There are two types of ‘regeneration’, passive and active.
During long motorway journeys, passive regeneration will occur. This needs no intervention from the engine control unit. Due to the raised exhaust temperatures on a long journey (temperatures between 350 and 500°C), the procedure occurs slowly and continuously across the catalytic-coated (with platinum) DPF. The catalytic-coated DPF is situated close to the Engine, therefore the exhaust gas temperature is high enough (500°C) to ignite the soot particles. Due to this soot is burned-off and is converted into a smaller amount of ash.
Active ‘regeneration’ is when the ECU intervenes when the soot loading in the DPF is calculated to be 45%. The procedure lasts for about 5 – 10 minutes. Specific measures are taken by the ECU to raise the engine exhaust temperature to above 600°C, these include switching off the exhaust gas recirculation and increasing the fuel injection period to include a small injection after the main injection. The soot particles are oxidised at this temperature.
The ECU will trigger a regeneration process, if for some reason this is aborted, ie. customer slows down, stops etc, the process will be resumed when regeneration conditions are once again met, above 60km/h (38mph). This will continue for 15 minutes.
If after 2 attempts of 15 minutes, a successful regeneration has not been possible, the loading will increase. At 50% soot loading, the ECU will continue to maintain maximum exhaust temperatures of 600°C to 650°C to cause a regeneration process. The system will try to run a regeneration process for 15 minutes. If unsuccessful, the system will repeat this process for a further 15 minutes, if still unsuccessful, the DPF light on the driver display panel will then be lit.
The owners handbook states, the DPF symbol lights up to indicate that the diesel particulate filter has become obstructed with soot due to frequent short trips. When the warning lamp comes on, the driver should drive at a constant speed of at least 60 km/h for about 10 minutes. As a result of the increase in temperature the soot in the filter will be burned off. If the DPF symbol does not go out, the driver should contact an authorised Volkswagen repairer and have the fault rectified.
At 55% soot loading the DPF light is lit on driver display panel. At this point the customer should follow the advice in the handbook. If they ignore this information and continue driving the vehicle until the soot loading reaches 75% without successful regeneration, additional warning lamps will light up. At this point the customer will also be complaining of lack of power, etc.
At 75%, regeneration is still possible with the use of the VAS tester. Only when the loading is above 95%, is it necessary to replace the DPF unit.
Operating Status System Response
45% DPF Load Level 1
Normal Regeneration
50% DPF Load Level 2
Regeneration at maximum exhaust temperatures
55% DPF Load DPF lamp
Regeneration from 60 km/h onwards
("See operating manual")
75% DPF Load DPF, SYS and MI lamp
Torque limitation, EGR deactivation,
Regeneration via VAG tester only
95% DPF Load Replace the DPF Unit
This is such an informative thread so thank you. I now assume my Italian tune ups if we haven’t driven far is of less use than watching the VAG DPF app and going for a longer drive if near a regen.
Hi WFM I've been using Archoil since April. No differences noticed but it's added for long-term protection.
Observations from today after some hard driving:
Passive regens do reduce both calculated and measured soot levels but only a small amount.
They also seem to start when exhaust temp is above 325C
Archoil has increased my average distance between active regen by 30 miles.
J
Passive regens do reduce both calculated and measured soot levels but only a small amount.
They also seem to start when exhaust temp is above 325C
Archoil has increased my average distance between active regen by 30 miles.
J
I have never seen a warning light in over 130k of driving in 3 diesel Yetis. Mixture of short and long trips.
Never seen one either in wife’s Diesel 1.6 Fabia which mainly does short trips and about 4K a year. Occasional 45 mile return trips to York seem to keep it healthy.
Is it really wise to monitor and worry about the spot loading which goes up and down. Only think that really matters is how much ash capacity is left. As one above still has some ash capacity at 200k most of us should never have a problem?
Never seen one either in wife’s Diesel 1.6 Fabia which mainly does short trips and about 4K a year. Occasional 45 mile return trips to York seem to keep it healthy.
Is it really wise to monitor and worry about the spot loading which goes up and down. Only think that really matters is how much ash capacity is left. As one above still has some ash capacity at 200k most of us should never have a problem?
140 bhp 4x4 diesel, 89000 miles, average consumption 52mpg tank to tank, all for just 9% extra. Bargain.
Update: on a 16-mile journey, at higher speeds the VAG DPF app went plink plink plink and the bottle shape went red plus half the arrows. This didn't last long but happened again later. I assume this was a passive regen as the DPF input gas temp went up by about 100 deg C for a short time when I hit 60mph. Full % is now 91%, so as we're going out on Monday, I'll keep the 'phone on. I hope I don't sound too obsessed! Bit like when B Gas gave us a free electricity monitor some years ago. I was obsessive about checking all the lights, how the cleaner speed increased power usage, kettle, cooker, freezer, etc. After three days I don't think I looked again or (as I might do now) even create a spreadsheet. And no, I'm not getting a smart meter to do the work for me!
The problem is for so many motorists they only think about mpg! They ignore the servicing and maintenance costs of modern diesel vehicles,with their particulate filters,and duel mass flywheels and numerous other costly parts which can be short lived.Diesels are not built like the reliable work horses of times gone by! Then there’s the question of price of the cars to start with,I think it was Honest John who pointed out that at 15,000 a year it would take a few years to recoup the extra cost of choosing diesel.
At 8.5 years old and 20-25,000 miles per year on each of the two main cars in my signature. Over 200,000 now on the Yeti - must update the sig.!
Then I'm sure a diesel remains the right choice for both me and SWMBO. And I'm thinking just as much about the CO2 emissions as much as mpg.
NOx are a subsidiary concern, as rain washes those out of the atmosphere fairly rapidly and they are very reactive, so breakdown into less noxious (appropriate word?) compounds easily - that's why AdBlue works. Whereas the higher levels of CO2 per mile emitted by petrol cars (in inverse proportion to their mpg) is of greater concern, as that stays around for centuries and destroys the planet. While the NOx just destroy the humans who are destroying the planet? (Incidentally, that is one of the things I agree with VW on, and why our Yeti will remain "unfixed". I'd rather keep the higher NOx and lower CO2 thanks).
The diesel engines themselves are still as reliable as ever. Its mainly the emissions gubbins attached that cause the problems. More recent DMFs, made to a stronger specification, seem to be much more durable. Two manufacturers supplied DMFs to the VW engine assembly lines. Sachs and LuK (a.k.a Schaeffler). There is much anecdotal evidence among the garage trade that the LuK units are more durable than the Sachs.
Petrol engine cars also have expensive catalytic converters that can and do fail. My last petrol BMW had a cat fail. It's brand new non-OEM cheapo replacement cost £250 and failed in under a year. Replaced that by risking a £350 second hand genuine cat from a breaker. That was fine! Till I sold the car 2.5 years later. (on 250,000 miles). New cat was £850+VAT list.
P.S. It's "dual" mass flywheels, not "pistols at dawn". Darn auto spell correct again no doubt! That has done nasty things to my posts several times.😉
Then I'm sure a diesel remains the right choice for both me and SWMBO. And I'm thinking just as much about the CO2 emissions as much as mpg.
NOx are a subsidiary concern, as rain washes those out of the atmosphere fairly rapidly and they are very reactive, so breakdown into less noxious (appropriate word?) compounds easily - that's why AdBlue works. Whereas the higher levels of CO2 per mile emitted by petrol cars (in inverse proportion to their mpg) is of greater concern, as that stays around for centuries and destroys the planet. While the NOx just destroy the humans who are destroying the planet? (Incidentally, that is one of the things I agree with VW on, and why our Yeti will remain "unfixed". I'd rather keep the higher NOx and lower CO2 thanks).
The diesel engines themselves are still as reliable as ever. Its mainly the emissions gubbins attached that cause the problems. More recent DMFs, made to a stronger specification, seem to be much more durable. Two manufacturers supplied DMFs to the VW engine assembly lines. Sachs and LuK (a.k.a Schaeffler). There is much anecdotal evidence among the garage trade that the LuK units are more durable than the Sachs.
Petrol engine cars also have expensive catalytic converters that can and do fail. My last petrol BMW had a cat fail. It's brand new non-OEM cheapo replacement cost £250 and failed in under a year. Replaced that by risking a £350 second hand genuine cat from a breaker. That was fine! Till I sold the car 2.5 years later. (on 250,000 miles). New cat was £850+VAT list.
P.S. It's "dual" mass flywheels, not "pistols at dawn". Darn auto spell correct again no doubt! That has done nasty things to my posts several times.😉
I'd totally agree that way too many owners ignore the servicing and maintenance though. In the mistaken belief that the manufacturers recommendations for the ideal driving patterns are also adequate for their own, low annual mileages.
Experience has taught me a high mileage diesel having spent its life on motorways, with an exemplary service history, is a far safer used car buy than a low mileage petrol with dubious service intervals every two years or 18-20,000 miles.
Experience has taught me a high mileage diesel having spent its life on motorways, with an exemplary service history, is a far safer used car buy than a low mileage petrol with dubious service intervals every two years or 18-20,000 miles.
I will defend my 7 year old 1.2 petrol Yeti, at least until it develops problems, on the emissions front
At its MOT in March this year the CO reading at idle was .020% against an allowed max of 3.5%
The HC reading was 35ppm against an allowable maximum of 1200.
And to defend Petrol engines further, I understand that new regulations are planned for ship engines. I think the date is 2020, but they will no longer be allowed to use heavy oil, and the resulting knock on effect will be an increase in diesel prices.
At its MOT in March this year the CO reading at idle was .020% against an allowed max of 3.5%
The HC reading was 35ppm against an allowable maximum of 1200.
And to defend Petrol engines further, I understand that new regulations are planned for ship engines. I think the date is 2020, but they will no longer be allowed to use heavy oil, and the resulting knock on effect will be an increase in diesel prices.
I'd like some help with interpreting the latest VAG APP results. Yesterday a regen had occurred, during a short drive on Monday, although the App wasn't on. Regen 26% (could it have been interrupted, although I wasn't aware of the fan running on Monday when parking). Soot mass 6.17g, miles since last regen 4, and time 24 minutes, oil/ash 0.01g, soot mass measured 1.23g. At what level of soot mass is the DPF 'full' and what is the difference between calculated and measured? Also, being a novice with our Android 'phone, how do I download a .txt file? As a postscript re ship's fuel, the new P and O cruise ship Iona is to be fuelled by LPG.
Jimmy, you should be seeing a green/yellow line between the top display zone (where the DPF “bottle” symbol is) and the top row of 3 digital information displays. That progresses left to right as the soot level increases. Together with a green / yellow percentage in the lower right corner of the top zone. When those get between 75 and 95%, I’m finding an active regen gets triggered, as soon as the other conditions are also met, such as exhaust temperature, engine speed, etc. and duration those have been over minimum for a regen.
I too am still seeking a set of high and low values for Oil Ash Residue that would lend calibration to the readings I get from the App.
Measured soot mass always seems lower than calculated in our car. I’m also still trying to figure out why that is so?
I too am still seeking a set of high and low values for Oil Ash Residue that would lend calibration to the readings I get from the App.
Measured soot mass always seems lower than calculated in our car. I’m also still trying to figure out why that is so?
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