DPF questions

[Lucas_R]

Questions for those using the VAG DPF app,

1. Anyone noticed -ve mg/km during normal travel? If so, under what conditions? (Excluding a regen cycle)

2. Any difference between measured soot mass vs calculated soot mass over the course of fill/regen cycle?


@Lucas_R: Do you swap back to VAG DPF when enabling a regen via Carista? I noticed Carista only monitors soot mass.

No I dont use VAGDPF anymore because its for Android only and my little cheapy Andriod phone stopped working. I have an Apple phone, so using Carista exclusively for the past few years and just monitoring soot mass and triggering regens when necessary.

I did have a look last night on the App store and noticed an app similar to VAGDPF called DPF monitor for VAG and its $10. So just out of interest I might buy that app and see if it works on my SQ5. Apparently works on CarPlay as well so if thats true it will be quite a handy tool to have.

DPF Monitor for VAG on the App Store

[Lucas_R]

DPF questions

Update on the DPF Monitor app for iOS Apple devices as discussed in my previous post above. It appears to look and work in an almost identical way that VAGDPF does - which is a good thing. So for those people who are on Apple devices, this is a good option and definitely worth the $10 cost for the app. It also works on Carplay which is great.

Only downside is that you cannot trigger a regen using this app - you can only monitor the DPF behaviour and health.

I will use a combination of this app and Carista going forward, with Carista being able to manually trigger a regen at a time that suits me (eg not when im 5 mins away from home after just spending an hour on the freeway at 100kph).

[Lucas_R]

And for comparison, here is a screenshot of the VAGDPF app on the same car. Note both apps have several parameters on my engine that cannot be read.

[GreyWolf]

Hi Lucas_R

Thanks for the update. I think I might trial the app as well. Out of curiosity what is your average mg/km when driving? (negating variation with load/condition). It appears any value > 350C Exh temp is in passive burn state.


It would be great for the other 1500+ views if anyone else can share some data to compare & baseline.

[GreyWolf]

@ Lucas_R

Out of curiosity have you come across any phone apps that have the ability to trend multiple sensor values in one graph (similar to vcds)

I have since discovered the sensors associated & difference between the calculated & measured soot mass.

[GreyWolf]

In an attempt to crack Enigma 2.0 (without directly talking to the programming Engineers), thought I would share my DPF observations from research & monitoring the VAGDPF app.

It would be great if any others could share their understanding / observations to compare & confirm DPF function.

1. DPF active regen appears to enable via soot mass calculated value 30-32g.
2. Requires min 20km continuous driving to complete cycle. (Open road obviously better)
3. Once the DPF regen is complete: soot calculated 4-5g soot measured 0-1g
4. mg/km value – referenced to the soot mass calculated value.
5. Soot mass measured utilizes sensors: dpf differential pressure, pre-dpf EGT, MAF.
6. Soot mass calculated: EGT & Lambda sensor
7. If soot mass measured is greater than calculated it will override the soot mass calculated (update the value) & enable a regen.
8. When driving if EGT > 350C soot mass measured will maintain value or go down as EGT increases (passive burn) however soot mass calculated continues to increase (+ve mg/km value).
9. Short trips or cold engine driving will increase soot approx. x4.
10. 35g > soot < 40g you get your DPF light. (Go for a scenic drive).
11. 40g > soot < 60g you get your glow plug / MIL. (Hope you have a quality scan tool)
12. > 60g (Damn $$$$)

Other DPF enable pre req's
- 90C Temp
- > 1/4 tank fuel
- > 60km/hr


Hopefully this helps others if having issues.

[Lucas_R]

Hi Lucas_R

Thanks for the update. I think I might trial the app as well. Out of curiosity what is your average mg/km when driving? (negating variation with load/condition). It appears any value > 350C Exh temp is in passive burn state.


It would be great for the other 1500+ views if anyone else can share some data to compare & baseline.

Sorry mate I haven’t looked at the data closely enough to know.

All I really use the app for is to not only keep track of regens, but also to make sure the regens occur after the same/similar distance travelled each time to keep an eye on the general health of the engine (a boost leak or fuelling issue will fill the DPF up much more quickly).

[GreyWolf]

I agree,

It is a great monitoring tool for the price. I use it the same way to record baseline & determine if there are any abnormalities presenting themselves or contributors to increased soot loading.

I imagine as the DPF ages & accumulates ash (from burnt off soot), it will obviously reduce in volume which will increase regen frequency. I suspect this is also factored into the regen calc.

If anyone can share or knows of
- current ash value for your driven km's
- the max ash limit for DPF?

This may help to determine an average suspected life of the DPF.

[GreyWolf]

Something else that may be useful for others.

- Using a phone screen recorder function / app to archive/capture the regen for future comparisons or troubleshooting.

I have noticed variations in the soot mass measured value utilising the phone screen capture function. One prior to the engine being turned off. Then on the very next engine start-up.

Any one else seen this or other abnormalities in monitoring?

[TyS_Au]

Hi All,

I have been reading this thread and a number of others over the recent months and appreciate everyone's time and input into making it a valuable resource.


We are one such case where we have gone into limp mode whilst towing a caravan and having spent at least an hour on the hwy prior to this occurring (without DPF light pre-warning).


This is our 2nd lap of the country in our V6 Amarok, same caravan, slightly more load with kids that are 2 years older now, and a bit more load, but the first trip we had zero issues, other than a sticky EGR Valve on startup through winter. (Needed to reset the fault each morning on our way back to WA after the first start of the day (for a week from Vic to WA), once car was warm no issues for the day. VW couldn't find a fault once we returned to WA and were back to normal driving.)
The dpf issue happened a 2nd time only a few weeks ago despite being on the hwy again (80-100km/hr) for 1.5 hours the day before. The day it happened we were driving the pass between Tyalgum and Nerang in the GC Hinterland.


Not sure what happened on the first instance of going into limp mode, after being on the hwy for such a long time, but since downloading the DPF V*G app (lifesaver in many ways after reading about it on this forum), I have found that the regens don't like to initiate if I am driving in manual mode.

I'm not sure if I am being skittish and not giving it long enough to occur after our recent issues, but when we are getting close to that 40g or 100% mark I haven't had it initiate in manual mode. If I leave it in the standard D or S-mode (need to test S-mode theory more), then the DPF Regen seems to occur and continue down to 6-9g, driving at variable speeds between 50 and 110 if we are on our way back to base and happily carries on with short traffic light stops etc once the process have initiated.



The first instance of any DPF issues on our current trip was literally the day after I picked it up from VW Wodonga after having the rocker cover and injector seals replaced for an oil leak (was a warped rocker cover). Drove back to Bright that day so plenty of km and opportunity to burn.

The very next day, driving from Bright to Mt Beauty the DPF light came on (1st time ever since new - then about 95k). Did the standard 15min drive etc light out. The light came on in exactly the same spot driving the pass to Mt Beauty a few days later, and again a couple of weeks after that. Bizarre.
- Had it forced regened in Melbourne as a precaution before we were on the road again and then inspected again by VW in Newcastle, no issues found and nothing to report.


Two weeks later, we were on the side of the M1 in limp mode just north of Evans Head on a stinking hot Sunday. No forewarning and after being on the hwy for about an hour (ample time to Regen).
- I had been driving in manual mode that day which has led me to be skeptical about the DPF going into Regen in manual mode.
- Had the vehicle towed to VW on the GC after having to do a massive ring around, follow-up calls etc and plead our case, being travellers etc etc. VW did another regen and I was told that nothing was wrong with the vehicle and it was down to our driving pattern/style (Ahem ?!?!), back and forth to VW Customer Care - no response or reply from our case manager for weeks. Unfortunately have lost faith in VW diagnostics and now seeking the wisdom of those who drive their VWs every day.


Anyway so we're at the point of monitoring the DPF via the DPF VAG app religiously which is really ridiculous when you're on the road and certainly meeting driving conditions. It's not normal for drivers to have to go to these lengths of monitoring their vehicles simply to stay on the road - but here we are.


A few things that I have noted and considered up until now:
1. The manual mode initiation issue.
- I still need to test this further but have found that the vehicle goes into Regen in D-mode fine at present.
- It would be good to know if others have noticed this?

2. There are no passive regens occurring when the vehicle has opportunity to do so. I'm not sure if this is normal or not, (A VW mechanic told me it is, but personally it seems ludicrous that the vehicles wouldn't passively regenerate at every opportunity, especially at hwy speeds/conditions to lower the levels for subsequent city driving. Our vehicle will only Regen when it reaches 100% of 40g. - very little margin for error for a missed burn.
- SO the theory is that due to the vehicle not undertaking any passive regens (when on the hwy for 1 or 2 hours and the level is below 100% or 40g, our vehicle does not choose to get rid of any buildup while it has the opportunity to do so.).
- Because of this, and our most recent limp mode experience exemplifies this, we saw the levels increasing while we were on the hwy for 1-1.5 hours, when we got to our destination we may have been close to 100% (we didn't check it as we were pulling into our camp for the next few days).
- The next couple of drives were steep hinterland drives where we were likely between 40 and 60km/hr for most of the drive (not consistent speeds) and went into limp mode with a full DPF the day after on an 80km/hr stretch about 20min inland from Nerang. Unfortunately due to the DPF teetering on 100% and not clearing when it is 25, 50% etc the margin for error to give it the exact conditions it wants to burn when close to full just don't occur sometimes. VWs literature states that the DPF warning should come on at 45% and then actively regenerate above that level, not let the levels accumulate to 100% as a number of other Amarok owners have also reported.
- We managed to limp to a VW dealer south of Brisbane and the sound service agent (Elliott) kindly offered to help out and initiated a Regen for us on a Friday afternoon (a level of service and goodwill I have yet to see any other VW dealer offer their customers).
- By the time we returned to Tyalgum (125km of 80-110km/hr steady driving) we were back up to 40g!

3. In my personal view, all of our monitoring etc should not be required. Especially for those who live outside of the city and are certainly meeting the driving requirements. A regular non-technical driver should be able to use their vehicle (for mixed use driving) without concern of going into limp mode in the middle of nowhere or towing a caravan etc (loosing power unexpectedly whilst towing is not a fun exercise).

4. We were also reaching 100% / 40g between 100-150kms which might highlight another issue. This was without towing but we were up and down the Sunshine Coast hinterland roads during that time. This may also have reduced our margin of error to allow for a full burn to occur as we were building up so quickly.
- I have recently added some LiquiMoly cleaner to see if we can clear up the DPF somewhat and I realise that there are varying opinions on this but after reading a lot of reviews I gave it a crack and it has started to improve on the km we are reaching before we get to 100%.
- I am looking to go through another cleaning cycle with another product soon to see if we can help this along further and would love to see our vehicle undertaking some passive regens.

5. As per point 3, there shouldn't be any special that a driver needs to do to get their DPF to regen other than reaching minimal operating temps and speeds. All the talk about dropping a couple of gears and getting the revs up to 2000-2500rpm etc is fine, but shouldn't this only be after the vehicle has given you notice that you need to go for a long drive etc with the dpf warning light?
- After watching a burn occur via the DPF V*G app, dropping gears etc makes no difference to the exhaust temps once a burn has initiated and really for normal and intended use, nobody should really know that a burn is occurring anyway? It should manage itself if given the opportunity to do so.
- Going for a random drive on the hwy in 5th gear every 2nd Sunday seems a ludicrous way to manage a vehicle for normal and intended use. Going for a regular 80-110 km/hr drive in auto going about your normal business should suffice if there are no underlying issues.
- With our present issue of no passive burns occurring, the random element of going for a "hwy burn" aligning with a 100% or 40g level to clear the dpf will have marginal success.

6. Has anyone considered, or know if it is possible to have the limit for an active burn to occur reduced from 40g or 100% on an Amarok down to say 75% or 80% to allow for a margin of error prior to reaching the limp mode limit? From VWs literature this should be around 45/50% but real world use seems to indicate that this isn't the case??



Anyway long story, but trying to build a picture of our recent experience as it might help fill some gaps for others.


I am now looking to purchase another scan tool that will allow us to conduct our own regens as the cycle of booking in with VW or being towed off the Nullarbor is not a viable option.

Have considered VCDS but we don't have access to a Windows laptop currently so am down to either Carista or OBDEleven. Have read through the options and other threads but am still trying to ascertain the following between the two:
1. Can you force a regen with Carista or OBDEleven (with required Pro Plans) without mobile phone coverage (or will we need a handheld Autel or similar device for this?
- if someone is able to test this for us with their phone in airplane mode etc that would be great, I know others have asked for this info.
2. Will OBDEleven allow on-demand regens whilst driving (like Carista does??)
3. I feel that OBDEleven is the closest match to having VCDS but the offline capability is my main concern.


Thanks, I appreciate any help.
Ty

[TyS_Au]

In an attempt to crack Enigma 2.0 (without directly talking to the programming Engineers), thought I would share my DPF observations from research & monitoring the VAGDPF app.

It would be great if any others could share their understanding / observations to compare & confirm DPF function.

1. DPF active regen appears to enable via soot mass calculated value 30-32g.
2. Requires min 20km continuous driving to complete cycle. (Open road obviously better)
3. Once the DPF regen is complete: soot calculated 4-5g soot measured 0-1g
4. mg/km value – referenced to the soot mass calculated value.
5. Soot mass measured utilizes sensors: dpf differential pressure, pre-dpf EGT, MAF.
6. Soot mass calculated: EGT & Lambda sensor
7. If soot mass measured is greater than calculated it will override the soot mass calculated (update the value) & enable a regen.
8. When driving if EGT > 350C soot mass measured will maintain value or go down as EGT increases (passive burn) however soot mass calculated continues to increase (+ve mg/km value).
9. Short trips or cold engine driving will increase soot approx. x4.
10. 35g > soot < 40g you get your DPF light. (Go for a scenic drive).
11. 40g > soot < 60g you get your glow plug / MIL. (Hope you have a quality scan tool)
12. > 60g (Damn $$$$)

Other DPF enable pre req's
- 90C Temp
- > 1/4 tank fuel
- > 60km/hr


Hopefully this helps others if having issues.

Will aim to keep an eye on these values to see what we get but currently no DPF Light in our case.

Have just written a long post about our issues if you have the time to have a look I'd appreciate your insight.


Thanks

[Lucas_R]

Just my 2 cents. I dont have a V6 Amarok, but a 2015 Audi SQ5 TDI which shares a similar V6 engine (3.0 V6 biturbo 230kw 650nm) and ZF 8 speed gearbox, and both cars are from the same era - so id expect some similarities in their behaviours. I have been monitoring my DPF regens for about 5 years and about 60,000km.

My car has no issue initiating a regen when in manual mode. in fact, I drive in manual mode almost 100% of the time because I dont like the lazy shift patterns when left in normal D, and S mode is manic.

Ive never had a passive regen initiate unless the DPF is about 85% full or more, and if/when a passive regen happens it will only be on the freeway (never pottering around town).

I have driven 3-4 hours uninterrupted on the freeway at 115kph with no regen occuring, then I get close to home and pull into a petrol station to fill up and the fans are going like crazy (ie ive interrupted a regen that the car has decided to start once I got close to my destination, instead of doing it during the 3-4 hours on the freeway!!). This behaviour of the car doing a regen when "it wants to" rather than when "I want it to" drove me nuts, so I was very happy when I found a way to manually initiate a regen.

Given you obviously spend a lot of time driving this car around the country, and have had quite a few DPF issues - id highly recommend the few hundred dollars to buy this dongle and then the $80 or so per year for access to the app on your phone. Using Carista, you can check your soot level and initiate a DPF burn manually. I use this every 400km or so in my car so I can make the regen happen and then I can drive at 80+kph for the 20 mins or so until the process is finished.

Oh....also. A regen will not trigger automatically if:

- any engine fault/emissions fault lights are on the dash
- fuel level is below 1/4
- oil temperature is below 80c

Also.....and this will potentially apply to you because you are towing a heavy caravan around. The regen can be interrupted if the exhaust temperature gets too high. I have had this happen before when doing a regen and I was too vigorous on the throttle and then I noticed the regen stopped when it was only about 1/2 way through the process. I later Googled it and turns out I must have reached a temperature threshold for exhaust temperature and it disabled the regen. So with the extra load you are putting on the vehicle by towing a heavy load + any hills you go up, means that you could be unintentionally and unknowingly exceeding this temperature threshold and causing the regen to stop.

[rgh0]

Just my 2 cents. I dont have a V6 Amarok, but a 2015 Audi SQ5 TDI which shares a similar V6 engine (3.0 V6 biturbo 230kw 650nm) and ZF 8 speed gearbox, and both cars are from the same era - so id expect some similarities in their behaviours. I have been monitoring my DPF regens for about 5 years and about 60,000km.

My car has no issue initiating a regen when in manual mode. in fact, I drive in manual mode almost 100% of the time because I dont like the lazy shift patterns when left in normal D, and S mode is manic.

Ive never had a passive regen initiate unless the DPF is about 85% full or more, and if/when a passive regen happens it will only be on the freeway (never pottering around town).

I have driven 3-4 hours uninterrupted on the freeway at 115kph with no regen occuring, then I get close to home and pull into a petrol station to fill up and the fans are going like crazy (ie ive interrupted a regen that the car has decided to start once I got close to my destination, instead of doing it during the 3-4 hours on the freeway!!). This behaviour of the car doing a regen when "it wants to" rather than when "I want it to" drove me nuts, so I was very happy when I found a way to manually initiate a regen.

Given you obviously spend a lot of time driving this car around the country, and have had quite a few DPF issues - id highly recommend the few hundred dollars to buy this dongle and then the $80 or so per year for access to the app on your phone. Using Carista, you can check your soot level and initiate a DPF burn manually. I use this every 400km or so in my car so I can make the regen happen and then I can drive at 80+kph for the 20 mins or so until the process is finished.

Oh....also. A regen will not trigger automatically if:

- any engine fault/emissions fault lights are on the dash
- fuel level is below 1/4
- oil temperature is below 80c

Also.....and this will potentially apply to you because you are towing a heavy caravan around. The regen can be interrupted if the exhaust temperature gets too high. I have had this happen before when doing a regen and I was too vigorous on the throttle and then I noticed the regen stopped when it was only about 1/2 way through the process. I later Googled it and turns out I must have reached a temperature threshold for exhaust temperature and it disabled the regen. So with the extra load you are putting on the vehicle by towing a heavy load + any hills you go up, means that you could be unintentionally and unknowingly exceeding this temperature threshold and causing the regen to stop.

There are three modes of DPF regeneration and people tend to use different and confusing terms for them.

1. Passive - this occurs when the exhaust gas temperature in normal operation is high enough to burn the carbon off in the DPF with no specific other action. This typically occures when driving on the highway at high enough speeds. This reduces the "measured" soot load in the DPF but appears to not affect the "calculated" soot load

2. Active automatic - This occurs when the engine ECU senses sufficent soot load to require it and the ECU then injects extra fuel to raise the exhaust gas temperature to burn off the soot. This is triggered by some combination of the "measured" and "calculated soot values and when other conditions as listed above are met. I suspect if you have driven for a few hours on the freeway and the active automatic regen kicks in when you slow down that the regen is being triggered by a high calculated soot value. An active automatic regen is probably interrupted when the exhaust gas temperature reaches sufficient value that it is no longer required and the paasive regen takes over.

3. Active manually triggered - This allows you to force a regen if the passive or active automatic regens in combination have not achieved the desired soot reduction. This is typically required when the car never reaches the conditions to do any passive regen or initiate an active automatic regen due to repeated very short trips or some fault condition stopping the automatic initiation.

[TyS_Au]

My car has no issue initiating a regen when in manual mode. in fact, I drive in manual mode almost 100% of the time because I dont like the lazy shift patterns when left in normal D, and S mode is manic.

Thanks, just want to check that it initiates regen by itself automatically or when initiated using Carista?

Given you obviously spend a lot of time driving this car around the country, and have had quite a few DPF issues - id highly recommend the few hundred dollars to buy this dongle and then the $80 or so per year for access to the app on your phone. Using Carista, you can check your soot level and initiate a DPF burn manually. I use this every 400km or so in my car so I can make the regen happen and then I can drive at 80+kph for the 20 mins or so until the process is finished.

Thanks Lucas, I have been tracking your comments on other threads using the Carista.

I was hoping to find out whether users of either the Carista or OBDEleven are able to trigger a manual regen without phone reception. I was tending towards the OBDEleven due to more retailers and AutoInstruct are currently on Backorder for Carista.

The downside of the OBDEleven is definitely locking out access to other apps eg DPF V*G so I'll need to keep running my other cheaper dongle to monitor everything whilst driving and then use the OBDEleven if needed for some specific work (or wait a few weeks and order the Carista.)

Have you been able to run a manual regen whilst in limp mode with the Carista?

Also.....and this will potentially apply to you because you are towing a heavy caravan around. The regen can be interrupted if the exhaust temperature gets too high. I have had this happen before when doing a regen and I was too vigorous on the throttle and then I noticed the regen stopped when it was only about 1/2 way through the process. I later Googled it and turns out I must have reached a temperature threshold for exhaust temperature and it disabled the regen. So with the extra load you are putting on the vehicle by towing a heavy load + any hills you go up, means that you could be unintentionally and unknowingly exceeding this temperature threshold and causing the regen to stop.

That is very interesting, it was an undulating section of the highway the day we had the issue towing so the additional heat build up may have contributed to the issue.



I appreciate all of your background info as well, it's certainly helped understand the nuances of our vehicle.

[TyS_Au]

There are three modes of DPF regeneration and people tend to use different and confusing terms for them.

1. Passive - this occurs when the exhaust gas temperature in normal operation is high enough to burn the carbon off in the DPF with no specific other action. This typically occures when driving on the highway at high enough speeds. This reduces the "measured" soot load in the DPF but appears to not affect the "calculated" soot load

2. Active automatic - This occurs when the engine ECU senses sufficent soot load to require it and the ECU then injects extra fuel to raise the exhaust gas temperature to burn off the soot. This is triggered by some combination of the "measured" and "calculated soot values and when other conditions as listed above are met. I suspect if you have driven for a few hours on the freeway and the active automatic regen kicks in when you slow down that the regen is being triggered by a high calculated soot value. An active automatic regen is probably interrupted when the exhaust gas temperature reaches sufficient value that it is no longer required and the paasive regen takes over.

3. Active manually triggered - This allows you to force a regen if the passive or active automatic regens in combination have not achieved the desired soot reduction. This is typically required when the car never reaches the conditions to do any passive regen or initiate an active automatic regen due to repeated very short trips or some fault condition stopping the automatic initiation.

Thanks, I was wondering why we had such a discrepancy between the two figures on some occasions. Strange that the Actual/Measured soot mass gets ignored though still resulting in the same outcome where the regens are triggered by a 100% calculated load more frequently than expected or what is actually there.

Is this a precautionary measure by the system running two measurement models and erring on the side of calculated mass to initiate an active automatic burn?

I wonder whether the sampling tube(??) between the two pressure sensors is the root cause of a lot of issues.
If this gets clogged resulting in more rapid buildup / pressure differential than what is actually occurring in the DPF (measured load)?