Diesel Particulate Filter for Disc 4 HSE SDV6

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Originally Posted by stray dingo

They don't regenerate until traveling at 80km/h for a period of time - not likely over dry grass

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thats only nissans way of dealing with it...

some vehicles will regenerate anywhere anywhen and let you know all about it by flashing up a warning light on the dash, cutting engine power output and then upping the fuel consumption. then when that doesnt work it'll put you in a limp mode (at even further reduced power levels) till you can pull over to the side of the road and let it do a stationary regen which can take upto 30 minutes a go and if you're having a really bad day will want to have a second go at. Then Just to make you really really pleased to have something that makes your exhaust cleaner on board it will stick you in limp mode untill you can get it into a dealer to have a DPF service done which if you're really lucky they'll be able to do maybe tomorrow. If you're not lucky they wont be able to do it because they dont have the gear and it will be a case of traying it to a dealer who can or getting a replacement DPF which will take, ahhh bout a week mate, more if they dont have one in melbourne and have to bring it in from overseas.


The kicker is really this...

Australia moving to the equivelent of the Euro 5 standard.
Euro 3+ gives a standard for the diesel that goes into the tank. It gets tighter for Euro 4 and 5.

With fuel compliant with the euro 4 spec you can just and only just (with current tech make the emissions requirement for euro 4 without exhaust treatment.

once you hit euro 5 exhaust treatment is pretty much mandatory thats where schemes like DPF and Adblue came in.

Australian fuel does not reliably meet EURO 4+ in some places were tank maintenance and integrity (induction of particulate matter through breathers) is not up to par the fuel will sometimes not even make euro 3. following the basic premise of CICO can you blame the DPF for having a hard time processing the emmissions of an engine thats not being fed fuel of the standard required in the first place?

I realise that LR in all probability have not included the DPF in our fleet because it saves them money because Australian emission standards currently dont require EURO 5 compliance they can get away with not fitting it. But just quietly I hope that the reason its not fitted is because they've done the research and know that fitting it has the potential to cause unwarrented breakdown issues as our fuel can't be depended upon to meet the prerequisites for the technology.

I'm not going to wade in on the cancer stuff and can't really comment on the tech aspects of the fuel standards and how and when a DPF works....but as an owner of a 2009 D4 SE with a DPF fitted, I can certainly comment on my experience.

My car runs clean, and has never even the slightest puff of fume behind it. The exhaust has a very different smell to diesels I'm used to, quite innocuous.

I've had mine 2.5 years and I've had two regens (as in warning light comes on) and yet I drove in heavy traffic every single working day. The only reason I got a regen was the fact that I travelled through an area with miles of roadworks and there had been a prange. Everytime I felt I should turn off the engine, the traffic would inch a few feet forward (plus it was very hot outside). I was standing still or moving at less than 5kph for well over an hour. I doubt most owners would ever have their car regenarate, if driven in normal to heavy traffic.

When the car did regen....I assume it did it when the car was rolling at a decend rate of knots, as this is the owner manuals recommended way of cleaning the filter and getting rid of the warning light. At a guess, I'd say the car doesn't regen when the light comes on, only after you meet the regen parameter...but as I said, I'm guessing there. Maybe it's only at a certain high level of blockage that the light comes on and the car is constantly doing minor regens.....dunno.

As far as the actual regen activity is concerned, to get the light to go out.......you don't notice a thing.....no smoke, no noise, no obvious loss of performance. If it wasn't for the light on the dash, you wouldn't know anything had occured. On both occasions the light went out within minutes of normal driving.....not 20 or 30.

What's other D4 owner's experiences, are they the same as mine?

Cheers,

Kev.

from what I've read of the way the landy does it...

IT fires up often and for shorter periods when the vehicles speed is high and engine load is light.

IT turns on post glow on the plugs, does a late injection and spits some fire down the pipe to get the DPF "on fire" then runs a couple of pots (in a rolling sequence) low on power to spit more air down the exhaust to let the burn in the DPF breathe.

It has 2 levels of higher burn off, 1 requires you to hit the button that tells the computer to initiate the heavier burn. It can be done while driving BUT it requires you to be in a certain driving pattern.

The next level is a stationary burn off where you're required to pull over (I think it will still work if you have selected a certain gear combo, 1/low I expect) and let the engine do its thing till the DPF pressure differential says its clear.

The last stage is a dealer initiated one and sticks you in limping mode.

Just this week past, diesel particulate matter was officially declared a carcinogen. Harmful exposure levels are more of an occupational than user concern, but that said, its hardly fair that we don't at least have the option in Oz when its available elsewhere, right?

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Originally Posted by Blknight.aus

does a late injection and spits some fire down the pipe to get the DPF "on fire"

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... over-rides EGR valve operation to ensure they stay closed then does a late injection to leave unburnt fuel in the exhaust gas to cause the catalytic converter to reach its maximum safe temperature to generate sufficient heat to burn the particulates out of the DPF.

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Originally Posted by Stuart02

diesel particulate matter was officially declared a carcinogen

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So what's the situation if they are collected in a DPF over time then all burnt in a concentrated short period? Are they any less carcinogenic? Are they effectively more?

yep, Im waiting for them to introduce a second "EGR" in the intake which is intended to bleed boost air from prior to the intercooler into the DPF to allow a higher power out during the Regen.

My 2012 defender does not have one and I am glad it doesn't. The book states it will clean every 800 odd K's and you will need to be doing about 80 clicks for it to work. And if your in the bush the thing will get hot and set the grass on fire and some in other vehicles already have. In fact there is someone who is manufacturing dummy ones that look exactly the same with ports for sensors ect. Better without them less expences later.
Probably should pedal a bike if we are worried about that.
Lindsay.

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Originally Posted by Graeme

So what's the situation if they are collected in a DPF over time then all burnt in a concentrated short period? Are they any less carcinogenic? Are they effectively more?

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What the DPF does is catch all the unburnt particles of fuel when enough of them gather the DPF's temperate us raised and all the coolected stuff burns off.

Its not as clean as the normal exhaust emissions of a DPF fitted vehicle when its not burning But its still cleaner than the emissions if you didnt have one fitted.

Here's a ball park analogy.

Take normal every day wood, you burn it and unless its really hot it smokes.

If you catch that smoke and condense it down you get soot. if you condense the soot enough you'd get coal the coal once burning burns cleanly. Its not as clean as if you'd processed the tree into coal in the first place and then burnt that But its still cleaner than just burning the wood.

roughly....

hmmm, my nasty suspicious mind is thinking 'propaganda' regarding the shock announcement that diesel particulate matter may cause cancer under certain circumstances.
Now we have financial masochist stirring the pot by singing the praises of a DPF.

In the light of reality, as pointed out our diesel fuel barely meets any consistant standard, and that Australian 4WDs are known to leave the sealed road, a DPF is not a desirable fitment from a reliability, practical, agricultural safety or cost of ownership viewpoint.


When did YOU remove your wasteful, cheap old-technology lamps, and replace them with the CFLs, - when it was mandated and you had no choice? - Or years ago when theyfirst became available ???

I reckon we should aquaint ourselves with the concept of the "fellow traveller" - the well-meaning but ignorant person who espouses and promulgates an issue without fully understanding the damage (or hidden aganda) being done...


Cynical older James in WA