Technical DPF management

[1stDucato]

Not having had any experience myself, I'd be interested to hear colleagues' approaches to avoiding DPF problems. I think I understand the basics (avoidance of frequent short/ low engine temperature journeys w/o longer periods at normal engine temp & highish revs) but I'm wondering about how people put this into practice & whether they find any of the available fuel addives worthwhile. I note that the only dashboard warning light comes on when the DPF is already clogged & that getting ahead of that requires one to 'feel' a downward trend in engine performance which I'm not sure I'll be aware enough to detect....

 

[FiatDucato250]

Not having had any experience myself, I'd be interested to hear colleagues' approaches to avoiding DPF problems. I think I understand the basics (avoidance of frequent short/ low engine temperature journeys w/o longer periods at normal engine temp & highish revs) but I'm wondering about how people put this into practice & whether they find any of the available fuel addives worthwhile. I note that the only dashboard warning light comes on when the DPF is already clogged & that getting ahead of that requires one to 'feel' a downward trend in engine performance which I'm not sure I'll be aware enough to detect....

From what I have read and been informed a long drive with a little extra high rpm around 20 minutes.
Also important to use the correct engine oil. Could be C2 or C3 ACEA standard.
To clear remaining deprees that cannot be burned away it can be required to dismantled the dpf filter and flush with water.

 

[bugsymike]

Both those grade oils are "low ash" which should help although you need the correct one for your vehicle.
On the smaller diesels I have seen benefits from DPF cleaner additive used on a regular basis 1/2 a can per tankful of fuel, mostly for vehicles used in stop start short town type journeys.
Ideally a decent run at engine speeds of above 2000rpm continuously for around for around a 30 mile trip I have seen clear a DPF warning light on dashboard, providing it hasn't been left to late.
Some diagnostic can read the ash content and pressure readings of a DPF to assess it's life. Also they may be able to do a forced Regen to try and clean a DPF.
Basically short , slow journeys are worse.

 

[lycopersicum]

I use the diagnostics to monitor when the next regen will be and I make sure it happens in good conditions, especially not letting it get interrupted. I watch it happen and I don't stop until it's complete. Sometimes this means taking the van for a drive for no other reason than doing the regen.

Outside of a regen, driving at higher temps and rpm is not by itself curative and will not decrease the clogging of the filter, it just increases the clogging less, per liter of fuel used, than a trip with the engine cold.

 

[1stDucato]

I use the diagnostics to monitor when the next regen will be and I make sure it happens in good conditions, especially not letting it get interrupted. I watch it happen and I don't stop until it's complete. Sometimes this means taking the van for a drive for no other reason than doing the regen.

Outside of a regen, driving at higher temps and rpm is not by itself curative and will not decrease the clogging of the filter, it just increases the clogging less, per liter of fuel used, than a trip with the engine cold.

Thanks for your input. By " the diagnostics" do you mean the info provided by an appropriate OBD Scanner & if so which one do you use ?

 

[bugsymike]

I use the diagnostics to monitor when the next regen will be and I make sure it happens in good conditions, especially not letting it get interrupted. I watch it happen and I don't stop until it's complete. Sometimes this means taking the van for a drive for no other reason than doing the regen.

Outside of a regen, driving at higher temps and rpm is not by itself curative and will not decrease the clogging of the filter, it just increases the clogging less, per liter of fuel used, than a trip with the engine cold.

What I said in #3 "Ideally a decent run at engine speeds of above 2000rpm continuously for around for around a 30 mile trip I have seen clear a DPF warning light on dashboard, providing it hasn't been left to late." in conjunction with additive this has cleared MIL DPF lights in my experience as it has allowed the engine and ECU to complete an uninterrupted Regen of it's own without stops which is often the problem.
By doing it this way the engine is fully warmed up in normal driving conditions, so a safer way of doing a Regen rather than a "Forced Regen" using diagnostics whilst vehicle is stationary which has caused overheating and other issues in some cases.
At the end of the day do what works for you.

 

[lycopersicum]

@bugsymike yes, we agree -- what I meant is, if no regen is due, then driving down the highway in 4th gear will not "clean" the filter.

If it's due / overdue, the ECU will jump on the first opportunity to run it. It will basically trigger instantly as soon as the engine is warm, speed above 50 km/h (ish) and revs above 2000 rpm. So it's good to provide it with some steady highway conditions for that.

Unfortunately what happens with vehicles used in the city is that the long overdue regen gets triggered on a fast section of suburban ring road that's too short to complete it (takes about 10 minutes), so it keeps failing over and over again.

@1stDucato I use an app on my phone with a V-Gate Bluetooth OBD2 dongle, if you go down that route, the choice of app will depend on your phone ie. iOS or Android.

 

[1stDucato]

Both those grade oils are "low ash" which should help although you need the correct one for your vehicle.
On the smaller diesels I have seen benefits from DPF cleaner additive used on a regular basis 1/2 a can per tankful of fuel, mostly for vehicles used in stop start short town type journeys.
Ideally a decent run at engine speeds of above 2000rpm continuously for around for around a 30 mile trip I have seen clear a DPF warning light on dashboard, providing it hasn't been left to late.
Some diagnostic can read the ash content and pressure readings of a DPF to assess it's life. Also they may be able to do a forced Regen to try and clean a DPF.
Basically short , slow journeys are worse.

Thanks for your input.
I've just come across a 2025 DPF thread in which you seemed to agree with @Neophyte's statement:
"The Fiat Ducato Type 250 with Euro 4 was not equipped with a diesel particulate filter (DPF) as standard.
At that time [2008/09], it was often an optional extra."
This makes me wonder if my 2009 reg 3L 160MJ actually has a DPF: is there a way to find out other than by inspection ( & I'm not sure what I'd be looking for anyway!).

 

[bugsymike]

Thanks for your input.
I've just come across a 2025 DPF thread in which you seemed to agree with @Neophyte's statement:
"The Fiat Ducato Type 250 with Euro 4 was not equipped with a diesel particulate filter (DPF) as standard.
At that time [2008/09], it was often an optional extra."
This makes me wonder if my 2009 reg 3L 160MJ actually has a DPF: is there a way to find out other than by inspection ( & I'm not sure what I'd be looking for anyway!).

A proper DPF has two small pipes tapped into it going back to sensor/s that read the pressure in the exhaust both before and after the DPF and send that to the ECU as part of it's measurements.
If you just have a particulate filter it will look similar to a small exhaust silencer.