Had my. L322 now for 7 years with a few “ yellow/ reds” on the dash. Decided to give it a run on a 19+ reading on the magic diagnostic ii tool and to my surprise the burn started at 40mph up a hill! This stopped however having reached a roundabout some 2 miles away and I carried on to my nearest M5 junction. I noticed on approaching the roundabout there that a burn had kicked in again and swung into the south bound junction with the PDF treatment continueing. Now down to an 11 meter reading at this point so it was decided to take the roundabout again and then head north to where I had started.
Now to the point of the story. Not much happened despite a couple of increased acceleration efforts up to 70 mph until reaching my initial junction when I had another burn show on the ii tool.
Not wishing to miss an opportunity at this point the L322 proceeded to the next junction (a shorter distance than the others) pulled round the roundabout to return to my starting point .

Here is the kicker! New reading 1.3 which must be its lowest reading since living in Somerset.

So this may help someone dealing with the dreaded Restrictive Performance on occasion.

Dave

JayGee wrote:

I’d avoid a forced regen unless you absolutely have to as it generates a lot of heat and stress on components. It really should be a last resort to fix a blocked DPF.

Baltic Blue wrote:

Forced regens are really only a last resort to be used if you get a red alert visit dealer type of message.

Is that correct, though?

Surely a Forced DPF regen just starts an Active regen, but when you want one to happen?

I don't believe there's any difference in exhaust gas temperatures or stress on the DPF core, etc.

In my experience, exhaust gas temps at the various sensors are the same during a Forced regen and an Active one. Additionally, temperatures during a Forced regen do not go beyond those specified in the LR technical literature. This observed in my case with a 3.0 SDV6, but I can't see the TDV8/SDV8 being any different.

Reading through the "System Operation and Component Description" for the 4.4 TDV8 L322, there are only 2 types of regens possible, those being the rather ineffective "Passive regen" and the "Active regen" we're discussing here, albeit manually called - or "Forced".

At the end of the day, Active regens are automatically performed roughly every 300 miles or so anyway, what's wrong with running one on your terms, when you know it'll have 100% chance to complete? The IID tool, for example, ensures the vehicle is moving and not stationary with the DPF or CAT glowing cherry red!

I'm not advocating running them 'willy nilly' all the time. That'll only increase oil dilution, but do it when DPF soot levels are near the trigger point for your vehicle, and you know full well you're about to blast down the motorway for 50 miles. Perhaps also, you know at other times that your driving route comprises many short runs.

Two questions then:
1) Am I correct that a Forced regen is *just* an Active regen but run when requested by the user
2) Did I say regen enough times...

Jon 1992 RR Classic 3.9 efi Vogue
2014 Disco 4 HSE
===================
Both my fatties now gone...
Previous: 2011 L322 4.4 TDV8 Vogue SE /// 2002 L322 4.4 V8 HSE /// 2009 Discovery 3 2.7 TDV6 XS /// 2004 Defender 90 TD5 /// 1993 110 V8 Snatch Landrover /// 2005 Discovery 3 2.7 TDV6 SE (Aus) /// 1990 110 Isuzu 3.9 County (Aus) /// 1976 Series III Trayback (Aus)

I regularly do the same 23 mile run from Conwy to Llanberis, which is half ( A55 ) at 70mph and half on a 50mph A road.
I know that an active regen kicks in at 19.2g on my car, but it can take 10 to 15 miles at 60+ mph which is most of the A55 before it gets started, but it’s still showing 10g + when I arrive, so an incomplete regen.
However if I activate a forced regen on entering the A55 the soot level is down to 1g halfway along the 50mph section and at the end of the trip when I check in live values it can be as low as 0.6g., so a full successful regen .
So ?? which is better for the car, partially complete Active regen or fully complete forced regen.??

I don’t see the point of doing extra out of the way miles to complete the Active regen when Iknow that the occasional forced regen will work so well.

Thoughts ?
Cheers
Mike. G reg 2.5VM Vogue Portofino red 1991- 1999
V reg 2.5td P38 Rioja red 1999- 2006
53 reg td6 Vogue Oslo blue 2006- 2015
11 reg 4.4 TdV8 Vogue SE. Baltic blue 2015- date.
https://www.fullfatrr.com/forum/topic56162...tty+affair

@ Baltic Blue - Mike, I agree with what you're doing.

I do the same thing, 'cos our Disco can do a lot of short runs, so I manage the regens when I know a particular journey will perfectly suit and soot levels are sufficiently high. Otherwise it'll have failed regens and that's not good... Trigger point on our 3.0 SDV6 seems to be around 30g (which seems a tad high), and I can get it down to 0.5g in 20 mins of driving on the motorway.

I perform the manual approach, as the car seems to flatly deny requesting its own Active regen until that 30g trigger point is achieved!

I've seen various stuff online saying a Forced regen is bad, but my point is, it's just an Active regen managed by the same ECU - it's just done when you want it to be done, which is a more informed decision than the car itself can ever make. Only the driver knows future driving habits, until such time that car's get more AI!

I'm happy for someone else to come along and tell me the technical difference between an Active & Forced regen, but from what I've monitored with exhaust temps - it's exactly the same process, and the car is going to do it itself at some point anyway!

Jon 1992 RR Classic 3.9 efi Vogue
2014 Disco 4 HSE
===================
Both my fatties now gone...
Previous: 2011 L322 4.4 TDV8 Vogue SE /// 2002 L322 4.4 V8 HSE /// 2009 Discovery 3 2.7 TDV6 XS /// 2004 Defender 90 TD5 /// 1993 110 V8 Snatch Landrover /// 2005 Discovery 3 2.7 TDV6 SE (Aus) /// 1990 110 Isuzu 3.9 County (Aus) /// 1976 Series III Trayback (Aus)

Jon,
I’m pretty sure from my experience that a forced regen uses a bit more fuel ( maybe same amount but for a longer time ?), but I agree that whichever temperature you monitor there is no difference in maximum readings, but I recon that a forced regen gets up to maximum temperature quicker and the burn starts much quicker, irrespective of soot level.

I wouldn’t recommend using forced regens too often, but really think that they are better for managing soot levels to avoid incomplete Active regens with the consequent oil dilution problem.

Mike. G reg 2.5VM Vogue Portofino red 1991- 1999
V reg 2.5td P38 Rioja red 1999- 2006
53 reg td6 Vogue Oslo blue 2006- 2015
11 reg 4.4 TdV8 Vogue SE. Baltic blue 2015- date.
https://www.fullfatrr.com/forum/topic56162...tty+affair