Just contributing my experience on this forum (as I have already on the Facebook ones). Regarding giving my DPF a clean whilst still on vehicle.. in the video towards the end you can see the whole load of smoke that came out! And this was on the second clean of the week. I figured doing it twice was worth while.





I also love the fact that when you tube was parsing the audio it thought the sound of the engine was music. I do have to agree on that one


For those who will respond and say 'hollow it out' - that idea is still on the table, but I do want to give the environmental helper a chance first.

James

2011 L322 TDV8 4.4

The car clears the soot itself by burning it at >600deg C and turning it into CO2 + a bit of ash during a normal DPF regeneration. 2012 TDV8 Vogue (L322)

Indeed that is the design (that it burns it off). However, as with all vehicles that have a DPF, ash accumulates and cannot be burnt off by the car itself. Big lorries were having their DPFs washed out long before they were even put in cars.

As the Ash builds up it reduces the capacity of the filter, until such a time that the yellow warnings (requiring a motorway drive) happen more frequently. The next phase of the issue is then that there is very little, or no time at all, between a yellow and a Red (go to dealer) error. The car can only guess the grams of soot in the DPF based on pressure differential. When there is excess ash, these pressure changes happen too rapidly and can cause the error to go straight to 'Red'.

I suppose it isn't too bad that the Range Rover got to 105k miles before ash became an issue.

As some background in case you havn't heard about it, there are lots and lots of Range Rover drivers hitting this issue. Broadly on other diesels this is true too. My various contacts and relatives in the motor trade all have stories across the brands.

My example of an L322 had a bad experiance in its past, where the previous owner had done lots of short journeys and the dpf regens had raised the oil level (by leaking diesel in) to such an extent that it ended up coming out the crank case breather. They had ignored the 'oil change due' appearing what might be considered too soon. (The L322 keeps a note of how much diesel it thinks it has spilt into the sump and requests sooner oil changes). As the oil had leaked out the crank vent (PCV) it had over fueled the car and of course put the DPF through hell. So mine probably has had a harder life than a lot of peoples!

The only way to remove ash from your DPF is to cut it off the exhaust and backflush it in a machine. 2012 TDV8 Vogue (L322)

Unless of course the chemical used is breaking down (or dissolving into the liquid) the ash into small enough parts that they pass through the filter during cleaning. There was an interesting video I watched a while back where someone tried various chemicals to see their effect on ash extracted from a dpf vs soot. One needed Alkali and the other acid I think. As a solution can't really be both, it will depend on which the Wynns fluid is. Of course, as you say their instructions direct using it off vehicle, where it would work as a cleaner, back flushing, in either case.

Whether the reason was a dilution of ash, or a break down of caked soot, certainly a huge amount of something came out my exhaust, considering the DPF was already 'clean' from a forced regen before hand. I mean the first time I cleaned it like this the soot level reading was 0.5 or so.. and the amount of matter that came out was massive. you couldn't see across the drive way.

I know that's not very scientific from a numerical point of view but for a qualitative observation it certainly means something came out, that the car's regen had failed to get out

James

DPF cleaners lower the temperature of when the soot particles burn off.
It doesn't remove the ash. 2018 SE SDV8 4.4 Byron Blue

JayGee wrote:

The only way to remove ash from your DPF is to cut it off the exhaust and backflush it in a machine.

Click image to enlarge

 2012 4.4TDV8
2000 Honda S2000

jtq4u wrote:

Big lorries were having their DPFs washed out long before they were even put in cars.

Begs the question….has it worked? Is the differential pressure V reduced? Is it regenerating normally? Gone to a good home: 2011 4.4 TDV8 Vogue SE Buckingham Blue with Ivory and clear glass = "Rory"
2025MY Defender D350 90 in Silicon Silver on coils
1974 Series 3 Lightweight = "Millie"
Many, many other Landies over the years
My preferred specialist: www.glenrands.co.uk
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PeteT80 wrote:

jtq4u wrote:

Big lorries were having their DPFs washed out long before they were even put in cars.

I’ve been driving trucks for just over 20 years and not once have I ever had a DPF “washed out”

Kot wrote:

PeteT80 wrote:

jtq4u wrote:

Big lorries were having their DPFs washed out long before they were even put in cars.

I’ve been driving trucks for just over 20 years and not once have I ever had a DPF “washed out”

Trucks mostly do long journeys and are worked hard

DrRob wrote:

Begs the question….has it worked? Is the differential pressure V reduced? Is it regenerating normally?

Indeed - the proof of the pudding will be in the eating.
When I have travelled enough miles I will be able to see if the interval between regens is extended by my cleaning activity.

Differencial pressure is harder to be sure of, as I have noted that at idle this is always a lot less than when under load with the turbo spooled up at the same revs. I guess that makes sense of course because there is more pressure coming out of the turbo!

For me success will be not having amber's and reds plus an increase in the regen interval.. suggesting an increase in capacity.

The service manuals suggest 300 miles between regens.. I have been getting around 70 - 100.
(about 3.5 to 5 miles per gram as some people choose to measure it).

I will post back after some time has passed to feed back as to whether it was a waste of time or not

Lots of info on here about DPF's and regeneration thereof. If you are getting regular warnings either your driving style is too many short trips or you have a airleak on the intake. If the DPF is full of ash and past it's capacity to hold soot without causing excessive back pressure then there is a specific fault code for this and not just a DPF full warning. 2012 TDV8 Vogue (L322)

Yeah I've been reading up on DPF content on this forum and the Facebook ones for about a year, as well as on every other source I can find. I even had a private email exchange with a guy who had talked to the RR design team.

I do also get the separate error relating to excess ash (DPF differential pressure too high). I don't think there is a 'I am full of ash' specific error on the L322, I think you are referring to DPF pressure too high.
I believe it does keep a record of the amount of ash it thinks it has, however I've never found anyone who knows the PID for it. I did end up finding the info on the amount of oil dilution which has proven useful so I can anticipate when it wants an oil change soon

I also smoke tested the stupid plastic manifold, and intake hose from the intercooler.. I didn't test further back to the intercooler to be fair. I did a you tube video on how to make your own smoke tester.
However I would expect a leak around those areas to show as value out of range for the MAP vs the air flow from the MAF. On other vehicles where I have fixed intercooler/air hose leaks I've always seen that error. The Freelander 2 and the Renault Scenic are a couple of examples. The Freelander 1 is an example of one that didn't, as it had no MAP/MAF comparison (maybe it didn't even have a MAP).. so instead you just got black smoke out the back when their hose went, from over fuelling.
I've also seen the MAP/MAF mistmatch detected on the L322 when the MAP sensor is blocked - so it does do a comparison of MAP vs MAF.

Every Land Rover I own seems result in a lot of learning. I keep them about 5 years each so I guess it is a 3 year degree, a 1 year masters and then a year of post graduate per model
I think its only when you mistakenly start to feel you know the thing that it is time to change model!

By the way I don't intend to pretend if the clean helped, and will try and stay away from the placebo affect. I promise I will own up if it is no better afterwards
Disinformation, after all, is worse than no information.
The video may still be useful though even in that case, for people who's dpf has ended up so full you can't even do a forced regen.

It stands true that there are lots of videos of professionals using Wynns on vehicle, but it is equally possible that they are not actually doing something useful and it is the 'reset to new dpf fitted' programming they do that actually fixes it, because a regen is then possible.