Help with DPF regen problems and deciphering VAG DPF data

[supramonsta]

Hi all. HELP, please.  

 

I am really getting tired of European cars...I love them, but am beginning to dislike them very fast due to the fact they dont seem to be able to do 10,000km's without dramas.

 

I have a 2013 Octavia VRS 2.0 diesel. Recently it threw a solid preheat coil lamp while driving. Next time I drove it it went away. Then it threw it again. I scanned it with Carista....P2102 Throttle Actuator "A" Control Motor Low Circuit. 

Then I got start-stop malfunction. Then engine light on with flashing preheat coil. Then the DPF light [which I've never seen before]. 

 

Now I also have P2463 DPF Restriction.  I also have manufacturer specific 05188, 05295, 09124.  I pulled the throttle actuator control off and although oily, it was only a layer....not soot as such. I cleaned it, the cogs were fine, it all looks OK. 

Put it back together, and same intemittent low voltage faults. But more worryingly..  I cant force a regen. I tried through Carista, did all the things i'm meant to....drove at a million miles an hour for a million miles.....blah blah.....

 

I just purchased VAG DPF but buggered if I can find decent instructions on how to decipher the data. Any help with this would be greatly appreciated.....I know that the bar up top saying 100% means it should regen , but what is the +73% [that worries me!!!!] Im not sure why i purchased the app, I have no idea about how to use it. The main thing I wanted to check was the oil ash residue........

 

Does anyone think that the low voltage circuit is stopping the regne?  Should I throw caution to the wind and buy a new TAC?   Just a note, this car has been religiously serviced its whole life prior to me buying it. The other thing to note, it is going through a crap load of oil.......maybe 2-3 litres every 10000 km's.  There is a definate layer of oil in the pipe from the turbo to the inlet manifold?  Not gunky though......

 

Sorry if I sound grumpy.....I am 😞  I have a 2010 Mitsi Pajero with 500,000 km's on it and never misses a beat. Anything I touch European gives me no end of headaches////  So sad, as they are such well appointed cars. Why can't VW get their **** together?

[Tivan]

Addition of percentage on top is because its not starting regen. That much you guessed yourself already.

 

Now as to why it does not do regen, I would also guess because of that error with actuator. Not 100% sure and someone here may know better for Skoda and this engine, but on some cars regen process can and is disabled while some other issues exist. Having an issue with TAC does sound like that would impact regeneration cycle logic.

 

Also, on your image, Oil Ash Residue value of only 19.1g makes no sense for the mileage of your car. Unless DPF was cleaned and this value reset in the past.

[supramonsta]

Tivan,

 

Thanks for your post. I appreciate your time and comments.   I too was mystified by the oil ash residue.  I am wondering though, as I brought it off a dealer here in new zealand and they acted like they were a private seller, if i had been played. Mind you, its not an easy process to clean the DPF??   What worried me was after I got the car I ran diagnostics from Carista and it told me that the engine faults had just been cleared [like immediately beforw I purchased it]. I have done about 13000km's since I purchased it and now all these troubles 

[Tivan]

There are ways to clean (or at least try) DPF yourself. And then there are specialist workshops that do that. Latter of course as better (and more expensive) option. Results of course would vary from car to car and the state of DPF it was in prior to the cleaning process.

 

Most will argue that professional cleaning is the option 1 before buying new DPF because of the price. And I would agree. Unless you live in a country where you can go with option C - remove DPF.

 

I am not familiar with Carista. I do use OBD11, and it never shows me errors I cleared myself previously. Then again, I never look for it. There is a log of course where I can access this data. But the fact that you saw this on your car and the problems you have now does sound fishy and I would suspect that dealer you purchased the car from has hidden some info from you prior to purchase. Although, it may just as well be that they cleared some irrelevant intermittent codes (like, low battery in key fob or similar less critical codes).

 

I would advise you do visit a trusted or well regarded garage in your area and bring the car in for inspection. You do not have to go on and start repairing the car part by part until fixed (that guess work is expensive). Rather try to visit one or more specialists if needed and form your own opinion on what to do, with their professional advices in mind of course. Someone else here may and probably will jump in as well.

 

 

Btw, since you said car was well maintained, has the car battery been changed and how old it is?

Edited 9 January by Tivan

[supramonsta]

Thanks again for your help. Excuse the short reply I'm on my phone now.

 

Option C is a possibility here in New Zealand. We do not test for emissions.

 

Interesting you ask about the battery, although I am unsure why.  That is definitely one area that is probably not that great. From fully charged and sitting in a garage unused for about 6 weeks it definitely struggled to start the car. Its not the best condition.

[ords]

Low battery voltage can throw up all sorts of fault codes & warning lights. How does the car run?  How old is the battery?

[supramonsta]

The car runs very well. It doesn't throw heaps of faults, just started with the low voltage fault from the throttle actuator.  

[supramonsta]

If anyone's still looking at this, could you comment on the fact that I have 35g calc soot mass yet its only been 300 kms since last regen?    does this seem extraordinarily high?

 

Im also wondering why I am missing the soot mass measured icon that others seem to have?

 

Also I am wondering that although my car is telling me to look at the handbook regarding a dpf clean, does this mean I have to take it to a dealer?  Does anyone know if I rectify the TAC fault if Carista will let me force regen?  I tried it yesterday but it didnt work. I gather its because of the TAC fault.  

 

I am now getting a fault P2463 DPF Restriction - Soot Accumulation. Im really worried this is the end of my car. The fix is about $8000 in NZ 😞

 

Any help appreciated.

[The_Bomber]

Hi, 

 

I have a 2014 vrs tdi. I’ve had some of the issues you described in the past with mine. Mine at its worst was going through 1litre of oil in around 300 miles. Dpf fault was constantly showing, there was oil in the inlet pipe. Around 2 years ago I ended up rebuilding my engine completely, blanked the egr and gutted the dpf and cat. Car running perfect since. 
 

Is taking the dpf off and emptying it altogether an option for you? May be a whole lot cheaper than 8k. My dpf was completely blocked solid.  

[supramonsta]

Hi [the bomber from Ireland  ]

 

The similarity of the issues on the same model car can be overlooked. 

 

How many miles were on yours at the time?

 

Did you find the source of the oil loss?  [Turbo?  Rings?  DPF blocked?]

 

Im interested you say that the DPF fault was constantly showing. Did that force the car into limp mode?

 

Yes, gutting the DPF is an option, looks like a bugger of a job though. It is definately on the list, after I try replacing the ASV [TAC] to clear that fault and then trying a force regen.

 

Only trouble is I am still back to a car burning ****loads of oil.  I have heard that a blocked DPF can cause excess oil consumption but I am unsure why.  

 

Thank you for your help

[The_Bomber]

Just over 130k miles at the time. Inside the cylinder bores were severely pitted/scored. The company that did the engine work suggested that the engine had possibly received “washed diesel” at some stage and that the acid used to wash the dye from the diesel had caused the damage inside the cylinders. Can’t be positive that was what caused the damage for sure. Had to be losing a lot of oil from the rings and seals as a result, which I imagine was in turn terrible for the cat/dpf. 
 

Yes the car was constantly going into limp mode then as a result. The egr valve and egr cooler (another joke addition to an engine in my opinion) were full of gunk at the time aswell. 
 

My asv was working fine, no issues. I put in a new turbo and injectors at the time aswell. 
 

Yes there’s a nice bit of work in taking the dpf off. 
 

I wonder is it possible to inspect the inside of the cylinder bores to see if there is any damage? 
 

 

[varaderoguy]

You can get cascading faults on VAG cars....i.e. something goes faulty and then it causes other things to stop working.

Its the fallback position on faults.

 

Right - splitting this down:  Your accelerator pedal (has died).  Common fault - seen this error on everything from Fabia, Octavias and Superb's.  Requires a new pedal....not expensive.

With the P2102 error, this will automatically disable Stop/Start.

 

DPF issues - its looks relatively healthy, but if your TDI engine is an oil burner as well, this will not help matters.  TDI engines (if they are abused from new IMHO) - will wear the piston rings.  2/3litres of oil per 10,000 miles is high'ish, but not terrible.  The VAG 'allowance' for oil consumption is 0.5L per 1000km - which is 1L per 1240 miles! or 0.81L per 1000miles.

I suspect that your EGR valve will be full of crud.  When was the last time the engine did a full re-gen (this is a Euro5 engine)?  Did you let it complete? When was the last time you also did a long/fast run?  I also a great believer on making sure you put in a cetane improver into your diesel (improves consumption, performance and cleans up the EGR valve).  You can either do standard diesel (with a cetane improver) or a couple of tanks of Super Diesel will also do the same thing....take the car on an Italian Tune-up afterwards.

 

P.S. when did you last do an oil and filter change?

Edited 15 January by varaderoguy

[supramonsta]

Thanks Bomber for all your info. It is very helpful for me to decide on a course of action. The time you have taken to reply does not go un-noticed

[supramonsta]

20 hours ago, varaderoguy said:

You can get cascading faults on VAG cars....i.e. something goes faulty and then it causes other things to stop working.

Its the fallback position on faults.

 

Right - splitting this down:  Your accelerator pedal (has died).  Common fault - seen this error on everything from Fabia, Octavias and Superb's.  Requires a new pedal....not expensive.

With the P2102 error, this will automatically disable Stop/Start.

 

DPF issues - its looks relatively healthy, but if your TDI engine is an oil burner as well, this will not help matters.  TDI engines (if they are abused from new IMHO) - will wear the piston rings.  2/3litres of oil per 10,000 miles is high'ish, but not terrible.  The VAG 'allowance' for oil consumption is 0.5L per 1000km - which is 1L per 1240 miles! or 0.81L per 1000miles.

I suspect that your EGR valve will be full of crud.  When was the last time the engine did a full re-gen (this is a Euro5 engine)?  Did you let it complete? When was the last time you also did a long/fast run?  I also a great believer on making sure you put in a cetane improver into your diesel (improves consumption, performance and cleans up the EGR valve).  You can either do standard diesel (with a cetane improver) or a couple of tanks of Super Diesel will also do the same thing....take the car on an Italian Tune-up afterwards.

 

P.S. when did you last do an oil and filter change?

 

By the accelerator pedal I gather you mean the ASV  [TAC?].   Im hoping its that simplistic, only thing is I had it off and it looked fine. Cogs were fine, and I cleaned it although it only had a layer of fresh oil.  I am going to try and activate it while its apart to physically see its travel prior to replacing it.

 

When you say the DPF looks fine I am not sure you can tell from that static shot while the car was not being driven.  I have read a post about a different make of car after someone had reset the DPF values. The main issue is how fast the soot levels climb?  I do not know where the "measured" soot level icon has gone that I have seen on other posts, but the calculated was climbing fairly rapidly when I took it for a short drive on the highway.  A possible indicator of this is the fact it says the last time it regened was 313km ago, and the soot mass is 35.6.  Isnt this high considering they are meant to regen every 300 miles [480 km's].  Then the Oil Ash Residue is way to low. I wasnt aware that DPF's are only good for 200 odd km's before they are stuffed. Nice of the car dealer not to mention this. I have apps that can read DPF Bank 1 Delta Pressure, Inlet pressure, inlet temp, outlet pressure, temp, etc, but I do not know how to decipher the data. I am really thinking that the DPF  was reset before I brought it without anything being done to it. They certainly did not replace it here in NZ at a cost of around 8k when I paid 10k for it.  I am wondering how the oil ash residue is calculated as that may give me an indication. 

 

As far as long fast runs go, thats mainly all it does. It usually does a 30 min trip at 100 km'h at least. Recently it has done to hour long trips at 100km/h.  It was regulary maintained all its life by specialised Euro dealers in NZ with the correct [expensive] low ash oil etc meeting VAG standards. The VAG allowance is shocking, but I am probably near that figure.  The strange thing is I spoke to the previous owner who said it did not use a noticable amount of oil??? [scratching my head]

 

Once again, many thanks for your help and any further advice appreciated. 

 

[varaderoguy]

8 minutes ago, supramonsta said:

 

By the accelerator pedal I gather you mean the ASV  [TAC?].   Im hoping its that simplistic, only thing is I had it off and it looked fine. Cogs were fine, and I cleaned it although it only had a layer of fresh oil.  I am going to try and activate it while its apart to physically see its travel prior to replacing it.

Its an "Fly-by-wire" type system.  The potentiometer fails (goes short). Mechanically - they don't exhibit any physical faults.

 

 

[supramonsta]

Thanks. Every other one ive read about exhibited physical issues.  The fault codes match what your telling me. I appreciate the information and your time.  I better start looking for a replacement 

[supramonsta]

UPDATE. [For the sakes of everyone who has helped me]

 

My soot mass was over 36g so I thought I should take the car for a run to get VAG DPF values while the car was running for troubleshooting purposes.  I gathered this would be my last drive due to not wanting to max out the DPF and make it impossible to to a forced regen. I have just truly realised how close this was, coutesy of information from the VAG DPF forum, https://www.applagapp.com/forum/viewtopic.php?f=4&t=13  

Apparently at 40g calculated soot its off to the dealer for a regen, and at 45g its a new filter!!

Anyway, to keep you up to speed my car apparently wasn't performing a regen due to a Throttle Actuator issue, and had been throwing the Glow Plug Coil flashing light and codes stating TAC stuck open, and TAC low voltage. I took it off and cleaned it, although it only had a wet oily smear inside. The gears and electronics were clean and undamaged. After putting it back on, I cleared the codes, but the P2111 TAC stuck open came straight back on. I took it for a drive and had engine light on, glow plug coil on, and DPF symbol on.

 

Today, taking it for its last drive before I was going to purchase a new TAC [had nearly done this a couple of times in last few days], I noticed the engine light wasn't on. The glow plug coil was flashing [and I am sure this had been solid], and the DPF light was on. I had to drive 8km to get to a highway, did about another 8 km on the highway to get some VAG DPF figures, and then headed for home before the soot mass got to high [i was monitoring this constantly]. 

 

Climbing up the hill [at about 40 km/h] and I looked at  the VAG DPF app and saw a LOVELY BRIGHT RED DPF!!  It was performing a regen!!!  

 

Now I'm actually wondering if after I cleaned the TAC, put it back on, and reset the codes that they reappeared because they were pending. I realise thats not possible? So maybe its an intermittent fault?  But it wasnt very intermittent before. I reset the codes 2 or 3 times to no avail. Anyway, time will tell.

 

Next question/s....any comments on the state of the DPF? Why does the Nox sulfur charge read zero?

 

I am still under the impression I may have had the wool pulled over my eyes here.  

• The oil ash residue is too low for a car having done 240 000 km's
• the mileage since last regen @345 kms is low considering soot mass was 36 g
• my calculations tell me it will regen again around 200 kms or less [barring any issues]
• AND ...... I have managed to get my hands on the full service records from the mechanics, and at the last service before the previous owner sold the car to the dealer I purchased it off, the workshop forced a regen. That was the only regen at service
• hmmmmmm...........

 

 

 

 

[Tivan]

Ash residue is the value you need to observe in relation to when to think about replacing the entire DPF. 

 

Soot value is normaly at 24g when active  regen is started. On your car for some reason it was unable to do that until now. 

 

Having this oil ash residue at only 19g at your mileage raises suspicion if that value is correct or not. If it is then your filter most likely is not for change. Although I am unsure how you can determine if it's correct or not at this point, educated guess from me would be that dpf was cleaned at some point and then was reset. If that is correct, what you now observe is clogged DPF that cannot perform active regen and needs forced one or replacement. That would be more appropriate state for given mileage of the car.