As this is the second time in a short period my DPF is full and I have no real clue to how the cleaning process actually works, I've gotten confused on how to get it to self clean.

One dealer tells me its revs that do it, another say is speed.

Last time I drove on the highway for over an hour, partialy at top speed. It did not work. In fact next day I drove for 20 minutes in the city and it dropped from "DPF full, visit dealer" to just "DPF full". Then I drove to a tank station 500 metres further and it cleared up when I restarted...

No, a month later, I have "DPF full", then "DPF full, visit dealer" then "Reduced engine power" in only a few minutes. drove 30 mins at max speed (with R.E.P. thats like 100kms/hr only).

I'm confused and annoyed atm.

The DPF re-generation needs heat to burn off the trapped soot particles and normally the ECM (Engine Control Module) realises the DPF is clogged and it tells the injectors to overdose with fuel to create heat. This heat burns the clogged filter out leaving a minute amount of residue thus freeing it up for a few more hundred miles.

They say any normal driving above 40mph is enough to allow re-generation and speed or RPM will give you the heat needed. I would hazard a guess you have a sensor problem.

I would say rpm rather than speed is what's needed

Iain

there is a sensor mod for the dpf have you had it done by the dealer if you havenot ask them to do this mod and you should be ok,to maintain filter i run mine once a week down the motorway for 20mins with the revs held at over 2,000 rpm your dealer should be able to give you a leaflet explaining how to maintain dpf filter  rainy-city
xs

Last edited by bigalf1961 on 31st Oct 2011 12:14 pm. Edited 1 time in total

There was a feature on Watchdog last week, and Nobody seems to know, each manufacturer had a contrasting opinion as did an 'Expert' they had on the show.
The most popular opinion was driving at over 3000 rpm constantly on a Motorway for 30 mins. (apparently stoping at traffic lights could put the process back to Square one)

That's why they don't have Traffic Lights on motorways

Junior wrote:

There was a feature on Watchdog last week, and Nobody seems to know, each manufacturer had a contrasting opinion as did an 'Expert' they had on the show.
The most popular opinion was driving at over 3000 rpm constantly on a Motorway for 30 mins. (apparently stoping at traffic lights could put the process back to Square one)

Junior wrote:

There was a feature on Watchdog last week, and Nobody seems to know, each manufacturer had a contrasting opinion as did an 'Expert' they had on the show.
The most popular opinion was driving at over 3000 rpm constantly on a Motorway for 30 mins. (apparently stoping at traffic lights could put the process back to Square one)

Sounds very eco-friendly and "good for your car"-ish....

zone30 wrote:

Junior wrote:

There was a feature on Watchdog last week, and Nobody seems to know, each manufacturer had a contrasting opinion as did an 'Expert' they had on the show.
The most popular opinion was driving at over 3000 rpm constantly on a Motorway for 30 mins. (apparently stoping at traffic lights could put the process back to Square one)

Sounds very eco-friendly and "good for your car"-ish....

The report on watchdog was about a Fiat 500 diesel not being suitable as a city car because it wasn't being blasted down the motorway to clean the DPF.

Unfortunately to meet new emissions standards the motor industry haven't quite got a decent working technology for this, I have now done 12,000 miles with no problem, very little motorway driving and 70% city driving to work and back. Perhaps I'm lucky (so far) or did the software update make a difference?

Here's the AA's take on how to re-generate

Quote:

On cars with a very high sixth gear the engine revs may be too low to generate sufficient exhaust temperature for regeneration. Occasional harder driving in lower gears should be sufficient to burn off the soot in such cases.

With this type of DPF regeneration will be initiated by the ECU every 300 miles or so depending on vehicle use and will take 5 to 10 minutes to complete. You shouldn't notice anything other than perhaps a puff of white smoke from the exhaust when the process is completed.

Zone30 - If your Freely is still under warranty let your stealer clean the system - maybe 2 or 3 times before he finds out he cant, then insist that they exchange the whole system which is what we had to do. If not under warranty then maybe you can get a LR goodwill exchange. LR are fully aware that their system does not clean itself as it should, and the procedure described in the book does not seem to cure the problem inevitably. True, there is a supposed to be a software fix and you maybe even be fobbed off with "Its a faulty sensor that is the cause" - tried all that and it don't work.

After our DPF whole system was exchanged we were advised by the stealer mechanic not to drive under 2000 rpm as this causes the DPF to not reach the correct temperature where it can function as it should. For us this means in practice that we can hardly ever use 6th gear on motorways (due to speed restrictions) and therefore not drive as economically as we would using 6th.

I fear, once you get the dreaded "DPF FULL Visit Dealer" displayed, maybe even with the reduced engine performance mode, you will eventually need a new DPF system. 2007 Freelander 2 HSE TD4 Manual with Premium Pack & Moonroof.
Stornoway Grey with Ebony Black Pleather, Clear Indicators, Body Side Mouldings etc.

I don't know if any of you have googled DPF cleaning, some good stuff to read, one company will sell you a can of jollop to put in the tank that lowers the temperature required to burn the soot particles, another one wants to just blow it out!
If you google DPF Removal it gets better, one even offers to remove it for you, then recalibrate the ECU to remove any software involving the DPF so the ECU won't look for it and trigger a fault, it then goes on to say that it may fail the MOT as the emissions will be higher.
I have also read that changes can be made to the ECU so that when the regen light appears it will over fuel the engine so more fuel is pumped in causing a hotter exhaust to burn the soot partials, wouldn't that increse more soot particles Either way it seems that there are quite a few companies looking to cash in on this.

Had this on mine - main reason faulty sensor but workshop manager did say that Landrover are introducing some fuel addative to do the job for you. Expensive? I asked.

He just laughed..........

However, after replacing and callibrating the dpf sensor I haven't had any other problems. So my money has stayed in my wallet....

DR There's always a way forward!

2008 Freelander Td4 GS - Stornoway Grey - Now Gone - Sob
2011 Freelander Td4 GS 150 - Rimini Red - in its place - Better x far x 4!!

Take a look here also: https://www.freel2.com/gallery/albums/userpics/11383/FL2_DPF.pdf

sounds a total piece of nonsense and certainly would not suit my style of driving.

to have to take your vehicle out on the motorway every week and drive it for 30mins over 2000rpm just to ensure it runs ok is utter balderdash.

if this was my only option for a diesel I would be going for a petrol engine quick smart.

Iain