- IndusD4
- Member Since: 28 Jan 2018
- Location: Sydney
- Posts: 698
Doesn't technology move on. But I doubt if that is used in our engines.
Ron
2016 D4 TDV6
IIDTool BT
- harrythespider
- Member Since: 19 Jul 2018
- Location: cumbria
- Posts: 404
As I understood the process, diesel is injected into the cylinders on the exhaust stroke, and not the compression stroke, consequently the post injected diesel is not ignited by either compression or by the spent fuel already in the cylinder, but by catalytic reaction. Therefor why can't the extra diesel required for regeneration be injected into the exhaust manifold or wherever else outside of the cylinder. After reading Andynoiseboys suggestions, injecting into the manifold appears to be one solution to the problem. Adding a supplementary injector to the existing high pressure system would not be expensive, nor would I believe adding the neccessary software to operate it as there is already software embbedded to overfuel on the exhaust stroke. In theory you could use all the existing sensors/ calculations/assumptions that the present system utilises but instead of activating the power injectors, redirect the command to the supplementary one. Or is that too simple?????
- IndusD4
- Member Since: 28 Jan 2018
- Location: Sydney
- Posts: 698
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I stand corrected, I thought it was burned.
Ron
2016 D4 TDV6
IIDTool BT
- chicken george
- Member Since: 31 Mar 2018
- Location: N. Yorks
- Posts: 51
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fuel is injected into cylinder to start the nox conversion process essential for dpf function early. it is not just the cheapest way of post injection but a essential part of euro 6
injecting it later/ after the turbo was used sometimes on previous euro bands but is not good enough for the top cleanest eu bands
so very many untruths on forums around this whole subject, believe no-one. including me
Chicken George, Land Rover owner for decades , and proud buyer of British products.
- chicken george
- Member Since: 31 Mar 2018
- Location: N. Yorks
- Posts: 51
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cripes dont start that 2 stroke thing off again, that and the must use a ctek charger everytime you park otherwise your battery will only last 7 years not 8.
Chicken George, Land Rover owner for decades , and proud buyer of British products.
- andynoiseboy
- Member Since: 26 Aug 2018
- Location: West Yorkshire
- Posts: 36
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Yep, the principle in it's most simplistic terms is that temperatures of 500-600C are needed to incinerate the soot collected in the DPF. In normal running conditions it will be too cool so additional fuel is burnt, not in the cylinder's ignition stroke, to raise the exhaust gas temperatures (and as a result, the DPF temperature) to a point where regeneration can occur. Essentially wasting fuel, ironically.
The electronics and sensors monitor the pressures before and after the DPF to assess whether it is considered to be free-flowing and therefore acceptably clear, then it stops the active regeneration.
Injecting the additional fuel late in the cylinders' power stroke does the job but risks fuel passing the rings and entering the engine oil - hence dilution, inevitably. Injecting the fuel into the manifold would negate that but would require addition hardware and control systems.
The current 'situation' is a result of trying to comply with regulations using an older engine design.
- DieselRanger
- Member Since: 12 Oct 2017
- Location: God's Country, Colorado
- Posts: 752
Yep, cost-benefit analysis. Had diesel sales not tanked in many countries due to Dieselgate, perhaps some automakers would have moved to a different design and that would have created a supply of parts to enable easier . One would have figured given the price points on JLR vehicles they would have made the choice to implement post-injection in the downpipe with an external heater to mitigate the oil dilution problem, but clearly that's not the case. Maybe we'll see something like that in the Ingenium 6cyl turbodiesel....
- AndrewS
- Member Since: 28 Apr 2016
- Location: Pembridge
- Posts: 410
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Well my dealer told me today that there is no issue with oil dilution at all in any engine.
Apparently it's down to faulty sensors throwing up the service indicator.
- Trevorb1
- Member Since: 08 Jan 2018
- Location: Nuneaton
- Posts: 275
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I would be changing my dealer as they clearly have no idea what they are talking about. Whether or not there is an oil dilution issue, the software uses an algorithym to predict oil dilution which is readable by the diagnostic system. If there is no actual dilution, then the algorithym is not predicting correctly, its nothing to do with faulty sensors.
My V6d had its first oil change at 5200 miles, oil dilution on pathfinder was then 7.2, no issues logged with vehicle, all systems working as designed.
24MY D300 Dynamic SE, Fuji White, Deployable Towbar, full size spare.
Gone 20MY SDV6 Landmark, Indus Silver, Deployable Towbar, 360 Cameras
- harrythespider
- Member Since: 19 Jul 2018
- Location: cumbria
- Posts: 404
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So thats JLR, owners and industry experts all agree that theres an oil dilution problem (well all except AndresS's dealer) But JLR are unwilling to provide a proper solution on what will soon be an obsolete engine. The trouble is, that until L462 reaches 3 years of age no one will offer an alternative/aftermarket solution for fear of voiding the warranty. The only hope is that other JLR marques that are out of warranty may have the same problem and would foster development of the solution.
Having read the numerous posts and included references I fail to understand why extra diesel needs to be injected into the system. If the only real criteria needed to allow regeneration is the provision of circa 600 deg C heat, why not simply introduce at the most effective position, a suitable in exhaust heater (I'm thinking induction coil) there are already available coils and systems capable of reaching the neccessary temp for the required period, all that would be required would be power source and operating software.
I'm guessing if it was that simple JLR (and other manufacturers suffering the same problem) would have done so by now.
- andynoiseboy
- Member Since: 26 Aug 2018
- Location: West Yorkshire
- Posts: 36
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It's a matter of obtaining a high enough temperature and doing that electrically has its challenges. I suspect the solution will simply be more frequent oil changes. Cheaper than redesigning the post injection or retrofitting some form of catalyst addition system.
- Guy
- Member Since: 10 Aug 2016
- Location: Sitting Down, Facing Front
- Posts: 27
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If the solution is more frequent oil changes, are they covered by warranty and/or the Service Plan? We seem to be hearing different answers from different dealers and, of course, the catch-all of "it's your driving style, sir/madam" seems to be a sneaky get-out...
