Motoring Discussion > Diesel Particulate Filters Miscellaneous
Thread Author: Bobby Replies: 53

 Diesel Particulate Filters - Bobby
I know there are lots of horror stories about these but has anyone on this forum ever had issues?
Last edited by: VxFan on Fri 15 Jan 16 at 10:07
 Dual Particulate Filters - VxFan
Dual?

Do you mean diesel?

If so, then I've had no problems with my DPF so far in the 11 months I've had my Astra diesel - touches wood. I've got a warning light that comes on if it's failed to complete a number of regenerations, and you must then do a decent run to clean it else it's a trip to the garage for them to do a forced regeneration.

You get to know when it's doing a regen after a while. Fuel consumption increases (handy to leave the fuel computer on instant consumption to give you some indication), engine runs slightly lumpy and louder, and in some cases plumes of smoke from the exhaust, although I've never seen any bellowing from mine, but a mate's Mondeo tractor chuffs it out like an old steam train.
Last edited by: VxFan on Fri 15 Jan 16 at 01:41
 Dual Particulate Filters - MD
Another reason to buy Petrol.
 Dual Particulate Filters - WillDeBeest
You get to know when it's doing a regen after a while.

It's just occurred to me that after eight months with a DPF I've never noticed it regenerating. Perhaps it hasn't had to; its regular trip is 25 miles each way and, M4 permitting, does at least some at full motorway speed, even if that does mean less than 2,000 rpm.
 Dual Particulate Filters - Crankcase
I could Google it, but is it right that a DPF traps all the nasty stuff so it doesn't get into the air as you drive about, then when it's full it just burns it all off wherever you happen to be, so it gets into the air as you drive about?

Or is that stick, end, wrong of?

 Dual Particulate Filters - Zero
>> I could Google it, but is it right that a DPF traps all the nasty
>> stuff so it doesn't get into the air as you drive about, then when it's
>> full it just burns it all off wherever you happen to be, so it gets
>> into the air as you drive about?
>>
>> Or is that stick, end, wrong of?

its designed to do it outside the house of electric car owners, the fast charger spur they have installed has a secret transponder to attract diesel cars to come and regen the DPF.
 Dual Particulate Filters - Old Navy
As I do not have to commute at busy times my car is used mainly in light free flowing traffic, often on motorways and I am a mechanically sensitive soul who believes in using the full rev range on occaision and I have never had a DPF light come on or been aware of a regeneration. My DPF is hot frequently enough to keep it clean. My next car will be petrol powered as my mileage has dropped below viable diesel use. Please do not reccomend anything with propulsion batteries! I do not want a submarine or milk float. :-)
Last edited by: Old Navy on Fri 15 Jan 16 at 08:23
 Dual Particulate Filters - RichardW
Sort of wrong end of wrong stick....

It traps the soot particles, but then when it's full burns them off into C02 and water, thus vastly reducing the particulates in the exhaust. We've got 2 DPF equipped cars, both have spotless exhaust tail pipes.

Only sign that the C4 Picasso is regenning is that the HRW comes on - although it does smell hot if stop soon after. The 307 has just a slight trailing throttle stumble when it's regenning (and the HRW comes on!).

Not had the warning on the 307 as it's used for a 30mile each way commute. C4 has given warning a couple of times as it is used more for stop start / school run.

Likely that Petrol particulate filters will be coming in a few years....
 Dual Particulate Filters - Old Navy
>> but then when it's full burns them off into C02 and water,
>>

I can only assume that my cars have had the type of use that keeps the DPF hot and it does not get "full".
 Dual Particulate Filters - Bromptonaut
>> Or is that stick, end, wrong of?

Sort of. The particulate is fine soot which causes respiratory problems and can get deep into the lungs. Harm is increased by the particles capacity to attract/combine other toxins and provide a vector for these to enter the lungs and possibly cross into the bloodstream.

Soot is trapped in the DPF and burned off, losing the harmful particulate structure. What comes out after DPF treatment is not completely harmless, but much less harmful than the particulates.

My 2013 Berlingo has now done well over 40k miles and other than it's obvious presence under the bonnet I've not seen or felt any indication of its activity. It has a mix of use from Mrs B's peregrinations as a supply teacher, local shopping and lots of longer distance stuff with and without the caravan. Mrs B will be on her PhD course from next month so the commute will to be Oxford Brookes campuses 2-3 times a week.

The Roomie must have one too and while I've only had it 6 weeks and 1200 miles again, I've seen no indication of it doing anything other than fact that there's not the remotest haze in the exhaust, even when caught in following vehicle's headlights. While it gets regular leg stretches on the M1 and A5 it does get a lot of use on my 7 mile commute to work. That comprises 5 miles of lanes and then another mile and a half on free flowing ring/feeder road in town. Last half mile is truly urban stuff with stop start for lights - but not usually jams as such. If I see it regen I'll try an remember to post a report here.
 Dual Particulate Filters - Zero

>> The Roomie must have one too and while I've only had it 6 weeks and
>> 1200 miles again, I've seen no indication of it doing anything other than fact that
>> there's not the remotest haze in the exhaust, even when caught in following vehicle's headlights.

It has a software one, a light comes on to tell you tis happening but...............

Its called a DPF - A Diesel Particulate Fooledya
 Dual Particulate Filters - Bill Payer
>> The Roomie must have one too and while I've only had it 6 weeks and
>> 1200 miles again, I've seen no indication of it doing anything...

Which engine have you got?

My wife has VW Tiguan with the latest EU6 2L diesel EA288 engine and it seems that in UK use they never get anywhere near hot enough to do passive regen.

Obviously VW where aware of this so the car does a mileage based regen at 465 miles, if the sensors haven't told it do one earlier. In practice ours is regenning every 2-300 miles. There's no way you can tell when driving - only if you stop in the middle of a regen and get out of the car you can then hear the cooling fan running.

I do have some concerns about quite how quickly the DPF is going to fill up with ash!
 Dual Particulate Filters - Bromptonaut
>> Which engine have you got?

EA189 1.6litre/90PS. Car is 11 plate so it'll presumably be Euro 5 rather than Euro 6.
 Dual Particulate Filters - VxFan
>> It's just occurred to me that after eight months with a DPF I've never noticed
>> it regenerating. Perhaps it hasn't had to

It'll do a regen at some point. As with any filter they have to be emptied regularly to maintain performance.
 Dual Particulate Filters - NortonES2
Just wait for the GDF to come into play. Euro 6 sometime will require petrols to incinerate their (mostly invisible) nasties…..
Last edited by: NortonES2 on Fri 15 Jan 16 at 10:37
 Dual Particulate Filters - Zero
>> Just wait for the GDF to come into play. Euro 6 sometime will require petrols
>> to incinerate their (mostly invisible) nasties…..

The Tesla is Euro 6 compliant, tho due to a mix up in reading the regulations it incinerates its passengers.
 Dual Particulate Filters - WillDeBeest
Only if there's a build-up, presumably. I'd imagine the system allows for a 'little and often' mode that burns off any residue when the opportunity arises - a mini-regen, if you like. People in other forums report rumbling noises, higher revs, hot smells, higher coolant temperature, drops in instant mpg or miles to empty; I've had none of these, so the stuff must be burning off before it can build up.
 Dual Particulate Filters - legacylad
The rumbling noises eminate from my rear seat passengers. As do the hot smells. Higher revs and drops in mpg are to be expected. My car doesn't suffer from higher coolant temperature. Once at working temp it doesn't fluctuate, regardless of revs or mph.
Are we still talking about DPFs or 330 ownership?
Last edited by: legacylad on Fri 15 Jan 16 at 11:06
 Dual Particulate Filters - WillDeBeest
The only one who mentioned 330s was you. Again!
};---)
Haven't you sold it yet?
 Dual Particulate Filters - legacylad
Still looking for the elusive 328 Touring. at least twice weekly on the BMW Approved used site, more casually on all other sites too numerous to mention.
Off to Spain next week for a couple of months, so will resume search when I return. Unless I decide to stay for longer....
 Dual Particulate Filters - Pat
>>It's just occurred to me that after eight months with a DPF I've never noticed
>> it regenerating<<

Neither have I, but I'm not sure if the V70 has got one or not!

W de B will know:)

Pat
 Dual Particulate Filters - WillDeBeest
Not required in most cases for Euro III or IV, Pat. 2009 was the year DPFs became the norm.
 Dual Particulate Filters - Pat
Damn, that's my excuse for making it growl now and again gone!

Pat
 Dual Particulate Filters - MJM
My Citroen C5 has one. I have not been aware of it regenerating at all in the 2 years I've owned it.
The need for regenerating is triggered by measuring the pressure drop across the DPF. When the drop reaches a certain level, extra fuel is injected on the exhaust stroke to burn off the residue. Elios? fluid is added to the fuel when the tank is filled to enable the burn off to occur at a lower temperature.
 Dual Particulate Filters - mikeyb
Used to be obvious in the C5 - slightly rougher running and the instant MPG dropped significantly.

Also used to run hot because if the regen was taking place when you stopped the cooling fan remained on.

Never really noticed it in the V60
 Dual Particulate Filters - No FM2R
>>Used to be obvious in the C5

On the subject of the C5, I had one of the very early ones as a rental on some visit to the UK or other. Took a bloke from the Fens out in it. It was damned awful and full of glitches. I have often wondered whether they got better but I never had the opportunity to drive one again.

Did they?
 Dual Particulate Filters - Armel Coussine
Cousin in Ireland had one a few years ago and it seemed a very nice refined motor. I didn't drive it though.
 Dual Particulate Filters - WillDeBeest
Much. I tried an early one too, and hated it. It had seats made from old washing-up sponges and a dashboard that could reflect in the windscreen whatever the outside lighting conditions.

Tried two of the facelifted one a few years later and it was transformed: better seats, better interior and much better looking outside. 1.8 petrol engine didn't suit it but the 2.0 diesel certainly did. Nice big hatchback too.
 Dual Particulate Filters - mikeyb
Mine was an 09 so one of the first of the current shape.

3 years and no issues or warranty work whatsoever. Lease company offered it to me for about trade price and I still wish I had bought it.

Fenlander had one at the same time and IIRC his experience was similar to mine
 Dual Particulate Filters - MJM

>>Did they? <<

Mine's a face lift 2007 hatch with the 2 litre 16 valve diesel engine and 6 speed Aisen automatic transmission. I find it well built, comfortable and effortless to drive. It's not a sporty thing but wafts along very well.
 Dual Particulate Filters - Bromptonaut
>> Also used to run hot because if the regen was taking place when you stopped
>> the cooling fan remained on.

Ahh... the 'lingo does occasionally have a cooling fan overrun on arrival at home. Puzzled me a bit as none of usual factors for high coolant temp - congestion, hard running or high air temp are present.

So perhaps I have seen evidence of the DPF in regen mode.
Last edited by: Bromptonaut on Sat 16 Jan 16 at 09:30
 Dual Particulate Filters - ....
>> >>It's just occurred to me that after eight months with a DPF I've never
>> noticed
>> >> it regenerating<<
>>
>> Neither have I, but I'm not sure if the V70 has got one or not!
>>
If it's 2005 or later 185PS EU IV then yes, it has a DPF, one that takes care of itself, no Eolys fluids or such like it just burns off when it needs to. If it's an earlier 163PS EU III D5 then it has two cats and no DPF.
 Dual Particulate Filters - Pat
It's the 185PS gmac, so I can still justify driving it like I stole it then:)

Pat
 Dual Particulate Filters - Mike Hannon
Our 2010 Accord has a DPF/FAP. We've had it three years and I've never been aware of it regenerating although, just occasionally, the fan stays on briefly when the engine is turned off while hot. I suppose our average journey is 20 miles or more, sometimes much more. The handbook says there may be white smoke from the exhaust during regeneration but I've never yet seen any sort of smoke at all.
As a result of this thread I was emboldened, yesterday, to stick two fingers up the exhaust tailpipe. To my surprise it was squeaky clean.

 Dual Particulate Filters - Runfer D'Hills
Never noticed it working on the diesel Qashqai I had for 80,000 miles or indeed on the diesel Merc I've had for 150,000. Never been troubled by them not working either.

Seems only to affect those who don't really go very far from what I can gather.

Cars do seem to like to be excercised in general. That of course raises the old question as to what is the better buy when choosing a used one. Older low mileage or newer high mileage for the same money?

Probably, I'd go with the latter but most people seem to prefer low mileage examples and will pay a premium for them.

I suppose it depends on the model, I've had some cars which at 70,000 have been getting quite tired and others which have shown little sign of wear at double that.
 Dual Particulate Filters - Old Navy
The answer to the OP seems to be that horror stories don't apply to us. Could this be because we tend to be motoring enthusiasts who use their cars as they were designed to be used?
 Dual Particulate Filters - Ted

I have no idea if the Vitara has a DPF or not. I noticed last year that she has sometimes held back a little on the gas when more power was needed..especially uphill with caravan on the hook................perhaps I was being told to give her a good thrashing.
 Dual Particulate Filters - rtj70
The Mazda6 I had must have often failed to regen the DPF because the oil level would go up. Never had an issue but I did insist on interim oil changes (or tell the lease company if the engine blew then I'm not responsible).

The fan on the VW diesel I had before this Audi A3 would sometimes remain on and always assumed it was DPF regen related.

My driving habits don't suit a diesel at times but usually BIK is lower overall for diesels. This Audi was cheaper. I take a slight hit on mpg but around town, especially in colder weather, I'm sure it's close to a diesel.

This morning, on the way to Bury for the Flying Scotsman, this petrol car warmed up much quicker than a diesel. It has a few things to make it warm up faster.
 Dual Particulate Filters - ....
>> This morning, on the way to Bury for the Flying Scotsman, this petrol car warmed
>> up much quicker than a diesel. It had a few things to make it warm
>> up faster.
>>
That's a bit of a generalisation. I had a petrol that took forever to warm up, a FIAT Coupe that was built to run at 155mph so had big air intakes which were a nightmare in winter in the speed restricted UK.

My current diesel only blows water vapour type smoke for the first half mile or so then there's warm air coming through the vents and the heated seats are burning away nicely. Only see a glow-plug light for a couple of seconds below -15C. Having said that, the KIA C'eed I had a few weeks ago took ten minutes to defrost at -2C.

The SAAB 900 V6 I had warmed up very quickly, temp gauge was showing normal after half a mile but the stem seals were shot at 74k miles.

I've noticed the last few cold mornings petrol engined cars stink from cold. I have to shut off the outside air vent. Do they change the petrol mixture recipe in winter too ?
 Dual Particulate Filters - tyrednemotional
...it may be a bit of a generalisation, but it is generally true.

You can't beat the laws of thermodynamics, and the greater thermodynamic efficiency of the diesel engine means less "waste" heat is passed to the cooling system; it thus takes longer to transfer enough to the cabin heating system.

Particular models do vary somewhat (as I can vouch after years of cold morning commutes in different diesel cars) and this is sometimes (as touched on by Z elsewhere) because the manufacturer fits an auxiliary or supplemental heater which (automatically) assists at low temperatures.

These may be, say, a small diesel-burning unit, or an electro-ceramic element (Ford dub theirs PTC), inserted in the cabin airflow (and shouldn't be confused with units dubbed "parking heaters").

I've had at least two cars with such a system, and they certainly do make a difference.
 Dual Particulate Filters - Old Navy
>> These may be, say, a small diesel-burning unit, or an electro-ceramic element (Ford dub theirs
>> PTC), inserted in the cabin airflow (and shouldn't be confused with units dubbed "parking heaters").
>>
>> I've had at least two cars with such a system, and they certainly do make
>> a difference.
>>

My Ceed had PTC heaters as do many cars these days. "Positive Temperature Coefficient" is not a Ford term but the type of heating element.
 Dual Particulate Filters - smokie
"Do they change the petrol mixture recipe in winter too?"

Used to be a manual effort, called a choke, didn't it?
 Dual Particulate Filters - Old Navy
>> Used to be a manual effort, called a choke, didn't it?
>>

The handbag hook, the only useful device that wasn't a cost option. :-)
 Dual Particulate Filters - CGNorwich
>> "Do they change the petrol mixture recipe in winter too?"
>>
>> Used to be a manual effort, called a choke, didn't it?
>>
I think he means at the pump. I believe the answer is, not in the UK. We use the same blend throughout the year. In cold countries they change to a more volatile blend during the winter months to aid low temperature ignition. They certainly do this in Canada.
 Dual Particulate Filters - Bill Payer
>> This morning, on the way to Bury for the Flying Scotsman, this petrol car warmed
>> up much quicker than a diesel. It has a few things to make it warm
>> up faster.
>>
Both our brand-new Tiguan and 11.5yr old C Class diesels remarkably blow warm air within a few hundred yards but while the VW seems pretty thoroughly warmed up after 3-4 miles the Merc needs about 15 miles.
 Dual Particulate Filters - Zero
>> >> This morning, on the way to Bury for the Flying Scotsman, this petrol car
>> warmed
>> >> up much quicker than a diesel. It has a few things to make it
>> warm
>> >> up faster.
>> >>
>> Both our brand-new Tiguan and 11.5yr old C Class diesels remarkably blow warm air within
>> a few hundred yards but while the VW seems pretty thoroughly warmed up after 3-4
>> miles the Merc needs about 15 miles.

They may have a separate diesel fuelled pre heater. My Touran did, and used to emit a puff of smoke from under the wheel arch sometimes.
 Dual Particulate Filters - Bill Payer
>> They may have a separate diesel fuelled pre heater. My Touran did, and used to
>> emit a puff of smoke from under the wheel arch sometimes.
>>

No - the Merc has a chunky electric booster heater in the block, but it takes so much current it only works when the car is moving - so it's no use leaving the car to warm up at idle. It can be turned on and off with the a/c button, or left to work automatically which it will do if the outside temp is less than 8C.

I'm not sure how the VW one works - many newer cars have PTC heaters in the cabin airflow.

But I thought most, if not all, diesels had some sort of supplementary electric heater in the engine coolant system - older Fords had a heater in one of the coolant hoses.
 Dual Particulate Filters - mikeyb

>> Cars do seem to like to be excercised in general. That of course raises the
>> old question as to what is the better buy when choosing a used one. Older
>> low mileage or newer high mileage for the same money?
>>
>> Probably, I'd go with the latter but most people seem to prefer low mileage examples
>> and will pay a premium for them.


I prefer newer higher mileage. Only time I opted for a below average mileage car it proved to be less reliable.
 Diesel Particulate Filters - Tigger
I have a 2007 Landcruiser, which has only just got to 59,000 miles. For a long time I was mostly working from home or taking the train, so it only got used at weekends.

I'm not doing a much higher mileage, and think about changing it for something more economical. But then I remember that I have no DMF or DPF.

So ... I've had it cleaned and dinitrolled. And the brake calipers rebuilt (that sitting around wasn't so good for them). ANd I'll probably run it for a few more years yet.
 Diesel Particulate Filters - Dave_
All my driving in DPF-equipped vehicles has been filter-friendly; stints of prolonged 60-70mph cruising on most days. I haven't had any DPF issues in 4 years of having them.
 Diesel Particulate Filters - DP
4 years of DPFs for me as well, and no issues to report. I didn't notice any kind of regen process going on at any point.

Just picked up an Audi A4 with an AdBlue nozzle inside the filler flap. That needs a top up every 7k apparently, and the engine will stop and refuse to restart if it runs out. Progress?

 Diesel Particulate Filters - rtj70
When you order and A4, you can opt for a larger AdBlue tank at no extra cost. Perhaps it will go further with the larger tank.

At least it's in the filler flap and not hidden under the floor of the boot, as it is in some cars.

How do you find the new A4?
Last edited by: rtj70 on Wed 20 Jan 16 at 17:15
 Diesel Particulate Filters - Runfer D'Hills
>> How do you find the new A4?


Easy, just find out where the nearest software company's sales conference is being held. There'll be loads of 'em.
Last edited by: Runfer D'Hills on Wed 20 Jan 16 at 17:28
 Diesel Particulate Filters - Avant
I had a test drive in an A4 this week - 2.0 TDI with S-tronic, which I think is the same as DSG.

Very impressive all round. The diesel was far quieter than any I've driven (new engine? better soundproofing?), and Audi seem at last to have devised steering that's both lightish and direct.

What Car have just made the A4 their Car of the Year - interestingly they go for the 3.0 V6 TDI as being worth the extra over the 2.0.
Latest Forum Posts