Peugeots first version of DPF diesels used a catalyst fluid during regeneration to burn off the soot (The first Ford diesel DPFs also used the same PUG engines) as the DPF was just a simple honeycomb with no special additives Inside.

Most other manufacturers chose to use a DPF brick which is impregnanted with catalytic material so no addition fluid is needed.

Normally this fluid should last between services so the topup was a service item, not intended to be filled regularly by the driver.

 

AdBlue is separate, it is not used for the DPF it is used for the SCR system.

   - First the DPF removes smoke/particulates

   - Afterwards the SCR system reduces NOx emissions.

 

Re: Passive Regens,

 

Monitoring with the VAG DPF app has never, ever, shown any passive regen in my vehicle, in fact, outside of an active regen, dropping a gear to raise the revs often COOLS the DPF as there is more airflow and presumably very little extra fuel.

 

Am I missing something here?

 

I have never seen the DPF warning light on 35k miles and the DPF seems healthy from the app data.

On ‎23‎.‎05‎.‎2018 at 13:03, kenppy said:

Reading through how the DPF works has made me realise that I did not sufficintly consider my usage profile. I changed from 2002 VolvoV70 to 2015 Skoda diesel thinking that I would get like-for-like comfort at a better economy.

 

l use the car maybe every other day (the only driver) for 2m trips and occasional once a month 60m, I totally failed to see that this was at odds with what modern diesels are for!  Nobody explained this -- but then I didn't even ask.

 

I assume that my driving pattern will knacker the car sooner rather than later?

 

As you suggest you are on the limit for owning a diesel in terms of useage/mileage & a small TSI petrol would have suited you better.

However, I think you will be ok as your 60 mile drive once a month or so should be enough to perform a regeneration if needed.

You may sometimes find that during short trips the engine is trying to regenerate (increased idle speed & fans running full speed when you stop).

However, as you only have a few trips short trips between before your next long run, it shouldnt cause a problem.

 

You might find sometimes that your fuel economy will not be as good as expected, because you get the best out of a diesel over long distances when it gets up to temperature & short trips plus regen attempts will use more fuel.

 

Just drive your car as normal unless you get a DPF warning light.

If this happens you can take it for a longer drive until the light dissapears or the Skoda garage can perform a manual regeneration for you.

As they should have advised you about diesel driving profile when you were buying the car you could argue that they should offer you this service for free.

7 hours ago, Gabbo said:

 

As they should have advised you about diesel driving profile when you were buying the car you could argue that they should offer you this service for free.

In total agreement with you but I'd also add that I have NEVER read a review (mostly Australian) of a diesel vehicle that  ever mentioned the possible shortcomings of a DPF equipped vehicle used only for short urban journeys. Or manufacturer's brochures either

Discussed in auto forums  of course, but this only reaches a small segment of the public already interested in the topic.

   22 hours ago,  Gabbo said: 

 

As they should have advised you about diesel driving profile when you were buying the car you could argue that they should offer you this service for free. 

In total agreement with you but I'd also add that I have NEVER read a review (mostly Australian) of a diesel vehicle that  ever mentioned the possible shortcomings of a DPF equipped vehicle used only for short urban journeys. Or manufacturer's brochures either

Discussed in auto forums  of course, but this only reaches a small segment of the public already interested in the topic.

 

I bought the car from a genaral dealer who pride themselves in not being pushy so I'm not surprised that I wasn't offerd any info. The problem is wholly mine for not being aware of these issues till I started reading here about the overheating  and came across the  DPF stuff.

 

So back to this and the warning light. This is what I get when I turn the ignition on. When the engine is on this goes out immediately. My book says that this light will be on momentarily and go off with the others, or go off. Must say that this is still something making me uneasy.

 

Is the fact that this stays on UNTIL the engine is running an indication that all is not entirely as it should be? Just a niggle I'd like to clear up.

 

Edited 29 May, 20188 yr by kenppy

The engine management light should go off when the engine is switched on, a fault would be indicated if the light stayed on constantly. The DPF warning light look so different and a warning would also appear on the Maxidot and under the car tab either way.

Just checked, the engine management light stays lit on my car until it's started. I would not have known this until you posted,  I normally just turn the ignition all the way forward and then let go to begin the starting process. 

59 minutes ago, durhamfisher said:

Just checked, the engine management light stays lit on my car until it's started. I would not have known this until you posted,  I normally just turn the ignition all the way forward and then let go to begin the starting process. 

 

Ah, that's good to know, I couldn't remember whether it was always doing that or this was the start of some nonsense.

Its a legal requirement for the OBD (engine managment light) to be ON when the engine is not running.

It should go off as soon as the engine is started.

 

If you have a real fault on the engine you will see the engine management lamp for emissions related faults or a flashing glow-plug lamp for all other engine related faults.

There should also be a text in the MaxiDot & in the vehicle status in the headunit to tell you a small info about the error & what action you need to take (e.g. stop immediately, service asap etc)

May I step in with an old post from VAG DPF App topic? My mileage right now is around 45thsd miles, and so far the oil ash progression, among other things, has been rather linear, so that software-estimated lifespan of my DPF would be at 240thsd miles. When I catch the DPF regenerating, I might leave the engine turned on, and, as explained below, the whole raised revs thing is just a waste.

 

Currently a VW Passat B8 owner (2.0 TDI 150 CRLB) , I can share my thoughts on this, as I've tracked the performance of DPF for almost a year now.

1) The paid version of the (VAG DPF Android) app is worth every single penny and then some, even if only a way to show some support for the developer. I use a cheapo no-name ELM327 purchased on eBay; don't see a reason to invest more in the adapter.

2) My regens also mostly start at ~90% soot load (23g) and finish around 20% (5g). The intervals are 180 to 300 miles, depending on city drives vs highway trips. Yet, on some occasions the DPF fires up at below 80%, and once it was a waiting game until 100+5%. Kinda frustrated about the premature ending of regens, yet see that most users here get the same results. If a regen starts and I know that my next drives will also be short-distance travels, I usually opt to take a short round-trip, just as a measure of caution in general.

3) To get a passive regen you have to either go mad on road (floor it deep - brake - repeat), or go fast. Like, really fast - at least in my experience. The only time I got a somewhat continuous passive regen was on German autobahn, at around 100mph - this was indeed the only time I managed to trigger the mandatory active regen due to 750km driven without one. This is ECU-dictated to prevent costly DPF-related mishaps, I suppose.

4) Aside the extra-injections during active regen, the heat in DPF is seemingly generated by turbo boost, NOT higher revs. Haven't tested this to the extremes though, e.g. going at 4000+RPM constantly, but I can assure that the widely lobbied constant drive at 60mph in 4th gear is nothing but pure waste - if anything, this way more soot is probably generated. As the turbo load is same or even less than in 6th gear, the DPF temps stay low. These are just my observations though, so you probably have to see for yourself. 

5) The oil ash load is somewhat of a mystic measure. So far I haven't noticed any stark changes in ash load dynamics. The developer has found out that max nominal ash load of the DPF equals 80g. I'm at 10g now at 30thsd miles (update - 13g at 45thsd). The thing to point out here is probably that the ash load is the ECU-calculated value, and the developer, as well as multiple users, has seen cars going OK at load twice or even triple that amount. So, another thing to take with a pinch of salt probably. Oh yes, and the measured load increases generally in between regens, not during or just after those. 

@willemson, thanks for sharing. Only once my car was driven for 300km at 160km/h so good to hear it happens at all.

 

As for ash - yes it's calculated and by some pattern. Connecting the VAG app to diff TDIs most have linear ash gain. Except for one car that was only driven only on short distances and mainly city driving. There the level was significantly more.

 

I also agree revs do not help, ash burn is mostly the same. What happens is hill climb however. Under such load ash is being burned faster according to the app.

 

I'm balanced person, like the car but this DPF is such a **** and ruins my experience. Almost totally to a level I drive my old car in town 95% of the time as it's a petrol.