Just purchased octavia and i was wondering why it was regening every 30 miles. When im driving the rev go just above 1000rpm and sometimes the fans stay on when i switch car off.

I recently read some topics on here and purchased the vag dpf app. I plugged it also to a vcds and no codes are stored. Surely the dpf shouldnt regen every 30 miles.

I use to own 2010 passat dsg 2.0tdi and owned for 10 years, that never did regens like this.

Looks like a old issue which the old owner has thrown on me(curse).

Below is image of dpf values.

Couple of things to check:

1) Oil Consumption. If you are constantly topping up the oil, then know that your piston rings are on their way out and oil is ending up in the DPF - and hence regen'ing.

2) Failed EGR valve. These usually fail open and will also cause all manner of crud into the DPF - causing it to block

3) It could just be that your DPF needs cleaning. This is a cost effective thing to do. One thing that needs to happen when you do this is that you need to reset the soot counter, otherwise DPF regens will continue.

4) Suggest running some super diesel or use a cetane improver (my recommendation on this last point usually end up in a flame war, but it work for me IMHO).

5) Take the vehicle on a long fast drive. A lot of the time, the regens's need to complete fully and it needs fantastic amounts of heat to do this....keeping the car running hard and fast (keep it in 4th if 5 speed and 5th if 6 speed). If DSG, then use manual and keep up the revs. Don't be afraid to give the absolutely foot flat to the floor beans (check your oil level first though).

Edited 28 November, 202528 Nov by varaderoguy
Updated

"Suggest running some super diesel or use a cetane improver (my recommendation on this last point usually end up in a flame war, but it work for me IMHO)."

Hi, many thanks for response, what did u use vpower or something else?

My car doesnt burn oil, i tested the egr on vcds and it completed.

7 minutes ago, Skoda672 said:

Hi, many thanks for response, what did u use vpower or something else?

Shell V-Power or any decent brand Super Diesel (Esso, BP or Texico) - Tesco fuel is the same as Esso fuel if that helps.

I used standard diesel with 10-20ml of Cetane improver from Hydra Int - https://www.hydra-int.com/DPB000K.html

Fill it up with super diesel and take the car on a 100 mile trip.....remember, constant high revs, switch off auto stop/start. That should clear it out.

Lots of foot flat to the floor action....it will probably be a bit claggy at first, but will improve as the car and exhaust gets hotter.

Edited 28 November, 202528 Nov by varaderoguy

Tesco Unleaded or Momentum 99 Super Unleaded & diesel comes from Greenergy who produces Fuel for ESSO in much of the UK and delivers it. But not all ESSO Filling stations with Petrol or Diesel are selling the same fuel as Greenergy produce /import. It can be the same, same spec / formulation, but that is not to Say from TESCO filling stations is the same as from the ESSO one. location location location.

Did this work for you

7 minutes ago, Evolution13 said:

but that is not to Say from TESCO filling stations is the same as from the ESSO one. location location location.

Yes, this is true.

Drove around 55 miles further today, continuous but local driving. Still hasnt regen yet. Few days ago i did forced regen while driving and also did adaptation for new dpf. Tested egr and it completed. (I dont know what im doing, lol).

So probably get 82 miles before regen this time. I will try vpower next time..

By the way does anyone know how much oil the crmb engine takes, 2.0tdi..

Edited 28 November, 202528 Nov by Skoda672

Fyi, my 2.0tdi 2016 which is now at 117k miles, does a regen around every 250miles (once per tank fill roughly) and has done so since I got it ~6 years ago.

Your ash residue looks very similar to mine from my diagnostic tools (VCDS).

I drive a lot on country B roads and A roads for work.

I always wait for oil temp to get to 60-70c using the MFD before giving it any right foot encouragement too and oil change religiously every 10k miles.

CRMB Oil volume is approximately 4.6litres for a refill.

Well filled tank up with vpower, done 35 miles continuously locally and the dpf is already 63% full.

Car drives lovely and smooth. Pulls like a train, I wonder what is actually causing this.

Not sure on the fault tbh, but for clarity here, have you continued to drive until it actually does a regen itself without interrupting the cycle at all. I'm wondering if that may clear it better.

I'm sure DPF when it regens should get to something like 400C or even more.

Edited 30 November, 202530 Nov by paulski

I think the regen completed around 13 mins, the dpf does get really hot according to the app. I continued to drive.

Edited 30 November, 202530 Nov by Skoda672

Look at the discrepencie between soot mass measured and calculated. Soot mass goes to negative. The old owner did say dpf was replaced 4/5 years ago, do you think it wasnt reset?

It goes to regen when soot mass calculated goes to 24g not the measured one.

I've seen so many videos about people replacing DPF's and not addressing the original issue, this could well be the case that the previous owner never fixed the issue that caused the original DPF to require replacement

But what can be cause, theres no water loss, no oil loss, no oil leak, egr test of vcds passed. Pulls like a train, very good mpg.