What RPM for DFP clean?

peking97

Having the DPF Pressure Sensor replaced tomorrow morning and intend to have a long run afterwards to clean the filter out. What RPM should I drive at and for how long in order to clear out the DPF?

demanufactured

Your looking at it the wrong way.
It doesn't matter what RPM the engine is at.
A good long motorway drive is all need to do, or get a static regeneration done .

peking97

Great to hear that news as I already have a long motorway run about once a fortnight so hopefully the DPF is fine and it's just the pressure sensor needs replacing. Car is in *limp mode* at present.

PaulKK

demanufactured wrote: »

Your looking at it the wrong way.
It doesn't matter what RPM the engine is at.
A good long motorway drive is all need to do, or get a static regeneration done .

Actually the revs have some bearing on things. I'm pretty sure the Octavia manual for example states to drive between 1800-2500 revs to resolve the dpf light, which in fairness it would be doing on the motorway.

MetzgerMeister

demanufactured wrote: »

Your looking at it the wrong way.
It doesn't matter what RPM the engine is at.
A good long motorway drive is all need to do, or get a static regeneration done .

Not necessarily. In mine it needs to meet all sorts of specifications like engine temp, coolant temp, no error codes for the engine etc. I use Bimmerlink app to monitor all the different items and I can select "Request DPF Regeneration" and you can see the exhaust gas temp shooting up to over 240 degrees C.

You have to keep driving at at least 100km/h for at least 20 minutes after it starts and I can monitor the soot ash level dropping.

I did it over the weekend and the soot ash was at 61g ( :eek: ) and by the time I was finished it was down to 11g.

It's important to note that not every long motorway run will induce a regen. It will only happen if the sensors tell the ECU that it's needed.

FR85

All depends on the soot level of starting out on the journey.

If your soot level is at a certain point then the ECU will trigger an Active Regen, once the Regen commences it's important to let it finish as to switch off your engine half way through will just leave excess fuel sitting in the cylinders which will eventually seep between the piston rings and liners the cause oil dilution and oil level to rise in the sump, thus meaning your engine components are being lubed by a mix of oil and fuel and it it's gets too much you will end up doing in turbo seals thus leading to a possible engine runaway.


Also, for an Active Regen to happen other criteria needs to be met such as a nice hot engine and a certain amount of fuel in the tank in some cases. A mate has an A5 that blocked itself even after good hard and fast runs and it was down to having less then 1/4 a tank, a DPF burn requires more fuel therefore if the car feels its doesn't have a sufficient quantity of fuel it will not commence the Regen.
When a Regen does commence some recommend turning on as many electrical items as possible (heated seats, demister, rear window ect) to add a load to the system, I have never gotten to the bottom of how this would be beneficial but quite a few have said to do this.


OP, have you an OBD reader to monitor the proceedings? If you don't you won't really know the status and you maybe just tearing up road burning fuel and adding miles to the clock with no benefit.....

cruizer101

MetzgerMeister wrote: »

It's important to note that not every long motorway run will induce a regen. It will only happen if the sensors tell the ECU that it's needed.

True for an active regen, but a decent motorway run will result in passive regeneration i.e. burning off of soot due to dpf naturally reaching a high temperature.

As I understand with enough passive regen you should never need to have an active regen

FR85

cruizer101 wrote: »

True for an active regen, but a decent motorway run will result in passive regeneration i.e. burning off of soot due to dpf naturally reaching a high temperature.

As I understand with enough passive regen you should never need to have an active regen

My 93 TTID lived on motorways, 90% of my driving was motorway and every 400-450 miles it did an active regen.

Passive or my understanding of it was that it has nothing to do with DPF heat or ECU intervention, it was just blowing dust/exhaust in the airflow exiting the engine, active was when it couldn't blow through anymore so the ECU then stepped in and things heated up. Could be miles off on that one I admit but that was my understanding of Passive.

cruizer101

My understanding is basically that soot/particulate matter builds up in dpf (how much may depend on driving style, I'd imagine more short journeys with colder engine results in more soot), and that is what is meant to happen to stop it being exhausted to atmosphere.
In order to burn off that soot the dpf must reach a certain temperature (think I've seen 500ish degrees mentioned).
In normal usage the dpf may reach that temperature, and it is more likely to happen on typical motorway journey 80km/h for 30min+, but not likely to happen on short journeys or trips where you don't go too fast as not enough combustion happening. (this ties in a bit to the turning on electrical items and a/c as more pressure on engine would mean more combustion so higher exhaust temps, but can't see it having much effect when active regen is happening).
So when that temperature is reached soot is burned off, how quickly I'm not sure, but its not going to be all burned off instantly, if a lot of soot it would need high temp for sustained period.

The other option for reaching that temp is active regen where extra fuel is pumped in in order to increase the exhaust temp.
This is triggered by the car detecting high levels of soot in dpf and potentially other conditions (e.g. the fuel level).
I do find it a bit odd as the car doesn't know the length of your journey and yet my understanding is stopping mid regen is bad. Ideally in my mind it would warn that it is required and let you trigger ti in some way.

So they are the two ways the soot can be burned off/removed, excluding taking the dpf off and carrying out some procedure. I have wondered could you just blowtorch the dpf a bit from the outside. And I thought with enough passive you wouldn't need active regen.

It does seem strange that if you had 90% on motorways it still did a regen that often, 450 miles is every tank, that sounds like some other issue at play. How did you know it was doing regen btw? warning light?
Also I'd caveat motorway driving with free running motorway, people could spend 2hrs crawling on M50 everyday and that would be bad for dpf.

Also I've come across dpf cleaner additives (wynns, stp) which claim to lower the temperature at which the soot burns off thus making it easier to burn off on shorter slower journeys. From the bit of research I did seems there is some evidence it may work and not complete snake oil.

FR85

cruizer101 wrote: »

My understanding is basically that
It does seem strange that if you had 90% on motorways it still did a regen that often, 450 miles is every tank, that sounds like some other issue at play. How did you know it was doing regen btw? warning light?
Also I'd caveat motorway driving with free running motorway, people could spend 2hrs crawling on M50 everyday and that would be bad for dpf.




I have an OBD reader called Esid2 which was designed by a former Saab techy guy so I was able to monitor it. Every 450 ish miles the soot level would go to 101% and a Regen would take place and once it started you got a feeling of rough running so at times I didn't even have to look at the readout, you could just feel it. Motorway was mixed between the M4/M7 and N7 so it wasn't piddling around town and the hours I work meant I had free reign , very little bumper to bumper.

In the 2l VW BMN engine I had previously again it would run funny and a purrrrry bassy note would come off the exhaust and again that did it at every 900 odd kms.
You get to feel it once you know the symptoms, in traffic a high idle and engine cooling fans were another symptom of the VW engine.

Wishbone Ash

I was told by a mechanic to drive to Dundalk and back in 3rd gear at 120km/h in a BMW E60 (about 10 years ago). It seemed to do the trick.

FR85

@cruizer101 as you also mention, stopping the engine mid regen is a no no, the extra fuel injected sits on the pistons as I mentioned and slowly soaks down between the rings and liners and then adds itself to the oil causing it to dilute and rise. You end up with everything being lubed in a diesel/oil mix which isn't good and if the level creeps up you end up doing in seals and risking a runaway.

The worst thing about knowing and being able to monitor it is that you find yourself at say 98%soot level so you drive on to trigger a regen and let it finish and before you know it you've added another 30-40 kms to your journey.....I'm a bit OCD!!!!

FR85

Wishbone Ash wrote: »

I was told by a mechanic to drive to Dundalk and back in 3rd gear at 120km/h in a BMW E60 (about 10 years ago). It seemed to do the trick.

While that may do the trick is it practical? As I just mentioned I found myself doing heaps of additional miles to keep the thing in check which burns more fuel, adds miles to the clock and wear and tear.



When reading about all the possible side effects and possible harm I ended up getting a delete and the difference is huge. Car runs better and the possible damage to the engine is reduced significantly.

Flood gates open to criticism now!!!

Toyotafanboi

FR85 wrote: »

While that may do the trick is it practical?

This while thread sounds impractical. Doing this via OBD and that via OBD, 1st gear this and 200km/h that.

The cars were designed to regenerate without driver input. Just drive the car as it was intended and it will regenerate itself.

I'm in my first DPF diesel car. I've put almost 15k kms on it now and never let regens cross my mind and it's been fine. My missus DPF diesel car we've had from new, put 110k kms on it, never given the DPF a minutes thought. I know one swallow doesn't make a summer, but if the driver has to be conscious of the DPF regeneration and force starting them then either the DPF system is faulty or the car isn't being driven as it was intended.

peking97

FR85 wrote: »

OP, have you an OBD reader to monitor the proceedings? If you don't you won't really know the status and you maybe just tearing up road burning fuel and adding miles to the clock with no benefit.....

No I don't have an OBD reader. The DPF pressure sensor was replaced this morning and all ok now but it appears to me that the problem was not in the sensor itself but in the short hose that comes attached to it. Looks like the hose was chafing against some other part and the real problem was actually an air-leak!

FR85

Toyotafanboi wrote: »

This while thread sounds impractical. Doing this via OBD and that via OBD, 1st gear this and 200km/h that.

The cars were designed to regenerate without driver input. Just drive the car as it was intended and it will regenerate itself.

I'm in my first DPF diesel car. I've put almost 15k kms on it now and never let regens cross my mind and it's been fine. My missus DPF diesel car we've had from new, put 110k kms on it, never given the DPF a minutes thought. I know one swallow doesn't make a summer, but if the driver has to be conscious of the DPF regeneration and force starting them then either the DPF system is faulty or the car isn't being driven as it was intended.

You are way out. Like everything else if they are not maintained and monitored they will bite you. If you just ignore it as you are and just driving the car as if ita not there you will eventually get problems. 110000kms on a diesel is nothing, on two cars I've four times that amount and have had problems!!!

Prevention is always better then cure and the OP is bang on to ask for assistance or reccomendations.

Toyotafanboi

FR85 wrote: »

You are way out. Like everything else if they are not maintained and monitored they will bite you.

What maintainance does a DPF require?

FR85

Toyotafanboi wrote: »

What maintainance does a DPF require?

They need to regen, they need to be allowed complete a regen, if they block up they may need a forced regen, they need low ash oil, from time to time they may need to be removed for a deep clean and at some point they will need replacement. Not looking after them leads to other problems.
Ive dealth with them on:
Seat Altea FR
Merc Sprinter
VW Crafter
Saab 93
Audi A5
Have all given problems or caused problem eleswhere. On the Sprinter you would be poisened in the cab when it was doing its thing and it would plume out white steamy like smoke.

Toyotafanboi

They need to regen, they need to be allowed complete a regen,

Just to be clear though, a DPF regeneration is part of the standard operation of that component and not a maintenance item in any sense.

An oil change or replacing brake pads for example would be a maintenance item, a DPF regeneration is not.

if they block up they may need a forced regen, they need low ash oil, from time to time they may need to be removed for a deep clean and at some point they will need replacement. Not looking after them leads to other problems.

And if my aunty had the right equipment, she'd be my uncle.

Basically what you're saying is that things can break and if they break there will be problems. That's fine and you're correct in that.

If you drive your diesel the way it was intended to be used, the DPF shouldn't need any driver intervention to operate bar simply driving the car.

FR85

Toyotafanboi wrote: »

Just to be clear though, a DPF regeneration is part of the standard operation of that component and not a maintenance item in any sense.

An oil change or replacing brake pads for example would be a maintenance item, a DPF regeneration is not.



And if my aunty had the right equipment, she'd be my uncle.

Basically what you're saying is that things can break and if they break there will be problems. That's fine and you're correct in that.

If you drive your diesel the way it was intended to be used, the DPF shouldn't need any driver intervention to operate bar simply driving the car.

Ok, all fair points but remember that a diesel was never intended to have a DPF, they were not designed to have a honeycomb baffle blocking them, they were an add on and the engine was manipulated to accept them, some went well, some were a disaster. The VW PD series for example, the two never went hand in hand.

A regen is part of standard operation on the condition that it is allowed to happen and complete, there is a thing called a failed regen and that is when standard operation ceases in that the owner turns off the engine during the process.
While you say it happens as part of normal operation....wrong, when the amber dpf warning light aluminates the owners manual on the VWs states, 4th gear at minimum of 3k revs for about 20 minutes, that in itself is housekeeping, its maintenance. If that light goes to red so does your bank balance and standard operation goes out the window!!!

Now yes things break, things wear out and a lot of DPF failures arise out of pilot error and buying the wrong car for their needs.
If you drive a diesel and just tootle around like you do a petrol you will have issues.
A lot of these issues arise from people not understanding what they are, how they work or what is required to make them work.

Us two would not be having this debate if (and I've said this on another post on boards) car makers would put a small light on the dash letting owners know when all this is happening, folks would know to keep going until the light goes out, failures would be halved.....but then how are ford/gm/vw ect going to make a profit on parts and repairs. Thats the argument and the OP would not have had to open this column to ask if that simple bulb was installed. Simple

Zatoichi

I have a Focus and was told you can tell if a regen is taking place if the instant fuel economy number jumps up beyond normal. I've never noticed it. Maybe it's just always doing a passive regen as I'm on the motorway almost every day with a straight run for 30mins at 100/120km/h.

CoBo55

I noticed in my superb it wasn't telling me to change up at the usual speeds, it was encouraging me to stay in 5th on the main road, when I arrived home it was racing slightly 1100 rpm with fans blowing like crazy and hot air everywhere, I just left it running on the driveway, went and had the dinner, came back out after about 30 mins and everything was back to normal. First regen I've encountered in 3200km. I noticed the adblue had dropped a bit in the display.

CoBo55

Wishbone Ash wrote: »

I was told by a mechanic to drive to Dundalk and back in 3rd gear at 120km/h in a BMW E60 (about 10 years ago). It seemed to do the trick.

What if you live in Dundalk... Only joking..

ofcork

Ive never ever noticed it in my avensis no fan running or white smoke nothing.

sunnysoutheast

Do DPFs not fill up, inevitably, with ash from the soot being burnt off, whether the regen is active or passive?

mgbgt1978

Yes, they do.The more Town driving you do the faster it fills up. Manufacturers will set an Ash figure of so many grammes. And you then have 3 options.
Replace it (big bucks).
Take it out and have it cleaned by one of the DPF Cleaning Companies (less bucks, but none of them can bring it back to new....possibly down to 20% ash at best).
Gut it and get it mapped out (cost really depends on your DIY skills).

peking97

mgbgt1978 wrote: »

Yes, they do.The more Town driving you do the faster it fills up. Manufacturers will set an Ash figure of so many grammes.

And how is the driver supposed to know when a regen is required or indeed how does the ECU know?

how.gareth

My 2018 vw crafter has been throwing up an orange dpf light weekly since it hit 4000km, it does a lot of city centre driving and maybe one motorway spin a day which then clears the light

demanufactured

My 08 mondeo has one of the early Dpf systems.
Uiu know when a regeneration is happening as there is a distinct smell of burning, heat all around the car, and fan running full pelt.

Audioslaven

CoBo55 wrote: »

I noticed in my superb it wasn't telling me to change up at the usual speeds, it was encouraging me to stay in 5th on the main road, when I arrived home it was racing slightly 1100 rpm with fans blowing like crazy and hot air everywhere, I just left it running on the driveway, went and had the dinner, came back out after about 30 mins and everything was back to normal. First regen I've encountered in 3200km. I noticed the adblue had dropped a bit in the display.

Yes the important part is not to turn the car off if you know that it is in the middle of a regen as it will complete with the car stationary.

mgbgt1978

peking97 wrote: »

And how is the driver supposed to know when a regen is required or indeed how does the ECU know?

I was referring to Ash. No amount of regens are going to sort out a DPF that has reached it's Ash Limit.
As for regens for soot. There is a soot level (around 24g for the VAG 1.6 tdci) that triggers a regen. If you are doing mainly M/way driving the soot build up is much slower, so the regen is triggered at a certain mileage.....either way it's triggered by the ECU and 90% of drivers won't even know it's happening unless they happen to be stopped and notice an increase in Revs and a lot of heat from the Car (especially from the exhaust).

ofcork

So is there a certain time or mileage that a dpf Wii be full of ash.

mgbgt1978

Simply put, no there isn't.
It all depends on the life the Car leads.
Constant town driving could have a DPF full at 100k (kilometers), while if it spends all day on the motorway (or just main roads) it could be 400k, and more, before it is full.
It also depends on the Car Model too. Some manufacturers are just better at keeping emissions down properly, rather than just relying on the DPF to do all the work.

Audioslaven

mgbgt1978 wrote: »

Simply put, no there isn't.
It all depends on the life the Car leads.
Constant town driving could have a DPF full at 100k (kilometers), while if it spends all day on the motorway (or just main roads) it could be 400k, and more, before it is full.
It also depends on the Car Model too. Some manufacturers are just better at keeping emissions down properly, rather than just relying on the DPF to do all the work.

True, I had a Mazda 3 1.6 and it used to regen every 300KM and as far as I could see based on pressure in the DPF (around 7KPA). I could never see the the level of PM.
My Honda Civic goes to between 1000KM and 1200KM and kicks off a regen between 10.5 and 11.5 PM.

I take the DPF filters out each year for a yearly wash and this has improved the Mazda filter in particular as the filter was doing a regen every 80KM before I did the first wash(that's over 2 years ago). Honda regens went from around 800KM to over 1000KM after the wash. I was also getting a ECU error around the regen taking too long/economy had dropped but this went when I did the wash on the Mazda.

mikeecho

Are products like this

Millers Oils Diesel Particulate Filter Cleaner & Regenerator
https://www.opieoils.co.uk/p-79253-millers-oils-diesel-particulate-filter-cleaner-regenerator-dpf-cleaner.aspx

Of any use as a preventive maintenance measure.?

cruizer101

mikeecho wrote: »

Are products like this

Millers Oils Diesel Particulate Filter Cleaner & Regenerator
https://www.opieoils.co.uk/p-79253-millers-oils-diesel-particulate-filter-cleaner-regenerator-dpf-cleaner.aspx

Of any use as a preventive maintenance measure.?

I'm always a bit skeptical of products like this and other fuel additives.

That said I did a bit of research and there is some evidence that there are catalysts that can lower the temperature at which a dpf burns of soot (and that is sound enough science that catalysts make a reaction happen easier).
The question is how much of these catalysts do the products contain, does it end up in the dpf if you put it in your fuel, does the amount that ends up in your dpf have any significant effect.

Some of them do get good reviews but I havn't seen anything too conclusive, and it should be possible to get some evidence as I think you can get the amount of particulate matter and dpf temperature via obd so in theory you should be able to see if they make a difference with a decent obd reader.

So eh, in conclusion I can't really answer your question, but I did get a bottle and put it in mine as the journeys I do probably aren't quite enough to be getting passive regen happening.

Audioslaven

mikeecho wrote: »

Are products like this

Millers Oils Diesel Particulate Filter Cleaner & Regenerator
https://www.opieoils.co.uk/p-79253-millers-oils-diesel-particulate-filter-cleaner-regenerator-dpf-cleaner.aspx

Of any use as a preventive maintenance measure.?

I would question their use. Personally, a physical remove of the filter and a clean will be better than any of this stuff but that's a bigger job than putting that stuff into the fuel tank.

mgbgt1978

mikeecho wrote: »

Are products like this

Millers Oils Diesel Particulate Filter Cleaner & Regenerator
https://www.opieoils.co.uk/p-79253-millers-oils-diesel-particulate-filter-cleaner-regenerator-dpf-cleaner.aspx

Of any use as a preventive maintenance measure.?

Hard to see how they can work. They have to go through the whole Combustion Process before reaching the Cat/DPF. So unless they can produce some sort of Magic Smoke it's a fair assumption that you are simply paying for the Advertising.
They don't even claim to extend the actual lifespan of a DPF, just that it will help the DPF to regen at a lower Tempurature. I can't see that happening (the ECU will only allow a regen above a certain DPF Tempurature), and even if it did.....so what ?

Irish Steve

mgbgt1978 wrote: »

Gut it and get it mapped out (cost really depends on your DIY skills).

There are indeed companies out there that will do this at the moment, and change the mapping to prevent the EML being triggered, but if things go the way that rumours are suggesting, it may not be possible to continue to get an NCT test for a car that has been treated in this way.

There are suggestions that the emissions test will be significantly updated to check more than just smoke emissions, and there have already been refusals to test where the tester has seen that the DPF has been gutted, and some (Mazda 3 comes to mind), it's very easy to see if the DPF has been doctored. In such a case, the only option was to get a DPF refitted into the vehicle, and get the original mapping restored to the Engine Management Computer.

mgbgt1978

Rumours are also suggesting that the emissions gear required to actually check if a DPF is present is prohibitively expensive and not worth it for the small number of Vehicles that may be caught.

Also, every Car is different. On some the NCT tester cannot even see the DPF, on others it's very visible but also quite easy to 'gut' as it's open at both ends (once removed).

Obviously it's up to Individuals to decide for themselves what road to go down, but at present if they have a DPF issue a removal could be the the most economical solution for some.

MetzgerMeister

mgbgt1978 wrote: »

Obviously it's up to Individuals to decide for themselves what road to go down, but at present if they have a DPF issue a removal could be the the most economical solution for some.

Why remove permanently when it can be properly cleaned once off the car despite the fact that it may be so bad a regen can't clean it?

demanufactured

MetzgerMeister wrote: »

Why remove permanently when it can be properly cleaned once off the car despite the fact that it may be so bad a regen can't clean it?

Because the complete idiots who do it buy a "daysul for de chape tax lad"
Not for its proper intended use.

mgbgt1978

MetzgerMeister wrote: »

Why remove permanently when it can be properly cleaned once off the car despite the fact that it may be so bad a regen can't clean it?

TBH I don't think anybody can properly clean a DPF In other words, back to factory-fresh. From talking to a couple of Friends that are in the Business they reckon the best you can expect is about 20% of Ash remaining after a clean. They won't mention this when advertising though for some reason .

Also if you're mechanically minded then it's a lot cheaper to gut it and get it mapped out. More power too....although that wouldn't be my main reason for doing it.

edit; A regen doesn't technically clean the DPF. It just burns off soot and leaves an ever-increasing level of ash. It's this ash that eventually clogs the DPF.

Audioslaven

demanufactured wrote: »

Because the complete idiots who do it buy a "daysul for de chape tax lad"
Not for its proper intended use.

TBH there was idiots also selling the cars to people and not informing them properly when they clearly should have examined the potential buyers driving style and match the car accordingly but its all about "johnny cash".

demanufactured

Audioslaven wrote: »

TBH there was idiots also selling the cars to people and not informing them properly when they clearly should have examined the potential buyers driving style and match the car accordingly but its all about "johnny cash".

Yup, this too.
People are still doing it now.
My brother bought a 2013 Passat diesel because he likes them and likes the power.
But he drives a couple of miles per day.

Audioslaven

demanufactured wrote: »

Yup, this too.
People are still doing it now.
My brother bought a 2013 Passat diesel because he likes them and likes the power.
But he drives a couple of miles per day.

I know a lady who travels 2KM to work each day. She is looking for a brand new car and the peugeot dealer is recommending a diesel to her. She was in the know and said a diesel does not suit her and he told her it does as it will be more economical, so some of the advice given is terrible. I think they have loads of diesel cars that they need to shift.

Sam Quentin

Has anyone tried this?

https://youtu.be/DTvcYpaTERE

Promising to say the least.

demanufactured

Audioslaven wrote: »

I know a lady who travels 2KM to work each day. She is looking for a brand new car and the peugeot dealer is recommending a diesel to her. She was in the know and said a diesel does not suit her and he told her it does as it will be more economical, so some of the advice given is terrible. I think they have loads of diesel cars that they need to shift.

Or they are clueless salesmen.