Dpf light on.

[blueskies13]

Hi all,

Living in s.wales UK. Currently struggling with dpf sensor problem (obd2 used to read) which points to pressure sensor.

Question being, where is the best place to pick up new sensor and can anyone recommend a good garage or independent to adapt new sensor (I can fit myself, although i understand this would have to be done just before adaption as the car should not be started without doing this)?

Also what's thoughts on buying a Ross tech VCDS as I intend to keep car for some time?

 

Thanks in advance.

 

Best. Blue.

 

09 Octavia scout 2.0 tdi 

 

[varooom]

What was the error you got?

[blueskies13]

Hi varooom, don't have them to hand as app not connected to obd2 reader.

From memory though it was p2352 (or close can't fully remember).

There was a stored dpf filter pressure 1, 2 and 3 code plus an egr code.

I'm pretty sure it's the pressure sensor  - will read again tonight or tomorrow and get back with specific readings.

 

Best. Blue. 

Thanks for the reply.

[varooom]

 

Be a good idea to find at least these 3x values.  Maybe your tool can do the adaption?

 

Anyhow, best to get all the fault codes present, and sniff about the live values.

[blueskies13]

Hi varooom, cheers again. The links look very helpful, trouble is I don't have a VCDS reader and am not at all familiar with using software, I'm more of a stilson and socket set man.

I have navigated my obd2 reader and pretty sure I can't do adaption with that.

I'll 're read codes tomorrow and post here - hopefully problem can be narrowed down.

I'm not sure whether I want to spend 300 on VCDS but it may well be a good investment as intend to keep this great car for some time yet - plus I've bought my son a vs polo - any recommendations?

 

Best blue. 

[varooom]

I dare say your tool can read measurement blocks, so try to use the guide linked to locate the values (nothing to loose but a little time trying)

 

Meanwhile, if you plan to keep in the VAG stable, a VCDS scan tool is £225 https://m.gendan.co.uk/product_VCV23_9.html

 

Or look about as I am sure other places sell it, HEX V2 is what you need, with at least 3x VIN

[blueskies13]

Thanks for reply.

I'll have a dig within the obd2 I've got tomorrow and certainly repost all details.

Cheers for VCDS recommendation, I have taken a look at this previously but haven't yet taken the plunge.

 

Cheers again. Blue.

 

[blueskies13]

Morning varooom, had a good look at obd2 functions and can't see any soot values etc - (it's only a cheapy 9£ thing borrowed off mate). 

Below is attached codes thrown up (3 in total).

 

Best. Blue.

[varooom]

Just be careful how much driving you do at the moment, you don't want to clog up the filter with soot.  In theory you shouldn't as there's a backup called calculated soot, but it doesn't always get correct values and you may overload the DPF and regen = fire so will be blocked.

 

It does seem you have a possible electrical issue with the circuit, just my quick look with eyes as busy for a bit now.

[varooom]

If you have a multimeter, that's what you could do with using right now.

 

Only 3 pins to check (might not be exactly as seen, was quick search)

 

[blueskies13]

Hi varooom, thanks for reply.

Much as your advice is im sure sound, extensive and again, much appreciated I think it's way above my skill level tbh. I've contacted a friend of a friend (ex vw/Audi technician) who will take my car in and hopefully sort it. He has VCDS and said it could also be temp sensor, he's also worried that dpf may be totally sooted up (as per your post) as I've run the car for some time with eml light intermittently on (let's hope the failsafe has worked and he can do a regen after poss sensor fix).

Thank you so much for your time and I hope I haven't come across ungrateful in this message as it couldn't be further from that.

 

Best. Blue.

[varooom]

All good, just all I ask if you can is post back progress updates so we can see how you get on, and if anyone else has the issue they can be assured of what to do to fix theirs.

 

Best of luck with it! 🤝

[blueskies13]

Yes of course, no probs at all.

Like I said it's been run for a while (4months) with light on/off (but been on permanent for 2 days) and only giving me limp mode last few days. Took your advice and not run her from now on and mates mate agreed with your advice.

I'm currently investigating how to manually clear dpf in order that I can salvage it (assuming it's kuput) so I'll get back to you on the outcome of that also (some differing advice from calling out the professional cleaners to injecting solution through port and allowing to soak).

Thanks again - I'll be in touch (maybe take couple of weeks though!)

 

Best - blue.

 

[varooom]

Mine needed some product down the DPF sensor port to clean out some "baked" on soot.

 

You can do a static regen, limp mode suggests you have 30g of soot, and at 40g you can no longer do a static regen, you will need some products to clean it.

 

Ask your friend of a friend how much soot it is reading if you can, more for completing the picture (as and when)

[blueskies13]

Yeah no probs. Will find out as much detail as I can and pass on - I'm sure he'll have no issue as I've talked to him and is very helpful. 

He did mention an upper limit for regen but can't remember what he said specifically - he did state that as been as its been in limp mode only twice I may get away with regen (seems your both on same page).

 

Will get back to you varooom. 👍

 

Best. Blue.

[varooom]

Memory bad 😜

 

24g up to 40g exhaust lamp on

40g to 45g is limp mode

[blueskies13]

Ahh ok. Cheers for info, I'll defo pass it on when dropping car off.

 

Strange one though varooom - I've never had the diesel particulate lamp light up (only the eml) and only the coil light (along with eml) when it decided to go into limp mode. I know there's a lamp for dpf on my dash as it lights up on pos 1 ignition  and then always goes out on start up (and does even though eml is now permanently on). 

Is there any significance to this do you think?

 

Thanks again for graph.

 

Best. blue.

[blueskies13]

I've read your graph wrong. Perhaps my dpf isn't at 40g yet? Let's hope it's retrievable!

 

Best. Blue. 

[varooom]

If you need the cleaning process, my friend did this for me (VAG master tech)

 

 

He's tried a few products, and this one he rates as it foams up, rather than a limp liquid that doesn't seem to coat the DPF.

 

Hopefully you don't need this process, but does work to clear soot.

 

[blueskies13]

Top man - great advice. I'll keep you updated. 💎

[blueskies13]

Hi varoom.

A quick update - all good with dpf filter, now fixed and regenerating.

 

I unfortunately don't have specific soot readings sorry as I've pretty much just let him crack on (didn't want to seem as if were pestering), plus he's doing a load of other long overdue work - haldex oil/filter, service, cam belt/water pump (so we've been talking about that too).

 

It turned out that the pressure sensor was faulty (as per my obd2 reader). I recall him saying that he checked fault codes with the sensor plugged in as well as detached, narrowing problem to said sensor. He physically blew down pressure pipe (to detect any back pressure) as he read soot figures to be reasonable (considering I had limp mode on a few times and eml light pretty much permanently on for some time - I think he assumed the worst scenario of totally blocked dpf). So pressure sensor adapted and regeneration went fine (although it wouldn't regen at first as there wasn't enough fuel in tank). No other codes thrown up.

 

I did read (obd2) an exhaust temp sensor issue when I initially had the light come on which I then cleared along with other codes. Explained to him that I saw this and he said that this could be faulty but it hasn't been thrown back up even after regen process so fingers crossed.

 

He used a genuine VW part I believe as he's had some differing results using aftermarket parts.

 

best blue. 

 

 

 

 

 

 

 

 

 

 

 

 

 

[varooom]

Understand about not pestering too much, a lot of the people I have spoken too since the new year have been swamped.

Hopefully now it will be much refreshed and stable for you now.  It does seem like you caught the DPF in time before it needed bigger intervention.

[blueskies13]

Yeah seems so although I haven't the car back yet so it's early days but I'm optimistic.

Thanks for all your time and effort.

 

Happy new year.

 

Best blue.

[varooom]

Fingers and toes all crossed then in that case.

[pikpilot]

I use a good app on my phone to monitor the dpf. It connects via bluetooth or wifi (your choice) to a OBD2 reader in the diagnostic port. It is called VAG DPF. There is also a free "lite" version with less features.

I thought this might be useful to you as it allows you to monitor the oil ash residue, soot mass both measured and calculated.

Here is a photo of my last use just after a regeneration. The bar across the top of the data fields and the 25% number show that my DPF is 25% full [at 73,000 miles].