JayGee wrote:

The trip should be pretty accurate vs calculated. The ECU is programmed to be 7% optimistic but you can reset this with the GAP IID tool and mine is now within <1mpg of the actual measured mpg.

I finally pulled my finger out and corrected my wheel sizes so my speedo is now correct. Next job is to brim the tank, reset my mpg, and then compare it to the next full tank refill for me to have a starting point before adjusting the setting in my IIDTool.

Or maybe I’ll change it so the car reports 40MPG+ and drive around with a false sense of economy  Currently driving: 2012 L322 SE Overfinch 4.4 tdv8

Past rides:
2014 Audi Q7 3.0d (good riddance)
2010 L322 Autobiography 5.0 Supercharged
2011 L320 HSE 3.0 sdv6
2014 Jaguar XF-RS 5.0 supercharged
2007 BMW 535D
2005 Mini Cooper S

https://www.fullfatrr.com/forum/topic59478.html

What input did you use for adjusting the speedo? The only one that worked for me was the last one called something like 'IPC' - with your tyres I'd drop it down (not up) 2 digits. 2012 TDV8 Vogue (L322)

According to the Gap FAQ it’s one of these two so I changed both… however it was the IPC setting that affected my speedo.



I am now almost bang on when compared to a GPS app, but intend to tweak it to under read a little as per all other cars. I.e. speedo reads 60 but actual speed is 58. Currently driving: 2012 L322 SE Overfinch 4.4 tdv8

Past rides:
2014 Audi Q7 3.0d (good riddance)
2010 L322 Autobiography 5.0 Supercharged
2011 L320 HSE 3.0 sdv6
2014 Jaguar XF-RS 5.0 supercharged
2007 BMW 535D
2005 Mini Cooper S

https://www.fullfatrr.com/forum/topic59478.html

Grateful for any help and advice from those much further down the DPF journey than I…

Had the P244B-68 (2F) Diesel Particulate Filter differential pressure too high (Bank 1) - algorithm based failure error code a few random times over the last 6 months. Cleared the code using my IID tool and never came back for ages so thought nothing of it.

Had EGR valve changed a few months back due to separate fault code keeping reappearing and not come back since, but clogged EGR could be related to DPF.

Went to LRO Show today and did 2 laps of the off road course at Tixover. On journey back to showground I got my first ever yellow DPF warning. Thought it wasn’t a problem and after leaving show was on dual carriageway and light went out so thought all’s well.

About 50 miles later between Milton Keynes and Buckingham the Red DPF light came on with no warning, as in no yellow first. Went into restricted performance and I couldn’t clear it so had to do 50 miles home like that.

When I got home I updated my IID Tool to get the Forced DPF regeneration function, filled to fuel tank and got on the M4 to run it. Soot went from 34g to 2g in about 20 mins. Excellent. Also cleared the codes and drove back home no problems on full power. Monitored soot all the way back and even went down further to about 0.3g before going back up to about 4g by end of journey with a few stops.

HOWEVER, now the P244B-68 code keeps coming back after I clear it. It seems that it’s not putting up a warning light but I can’t get rid of the code.

What do people on here think might be happening and what should I be testing or checking for?

I’ve got another long motorway run tomorrow so can monitor values on the journey.

Thanks in advance for any help!!

Andy Andy

2010 4.4TDV8 Vogue SE in Santorini Black with Ivory interior
2017 Audi SQ5 3.0 V6T Quattro in Volcano Red
2001 Audi Allroad 2.5 TDI manual with low-range in Highland Green. Currently SORN whilst undergoing some serious restoration!

This is the WM entry in the DTC section for quick reference! Andy

2010 4.4TDV8 Vogue SE in Santorini Black with Ivory interior
2017 Audi SQ5 3.0 V6T Quattro in Volcano Red
2001 Audi Allroad 2.5 TDI manual with low-range in Highland Green. Currently SORN whilst undergoing some serious restoration!

Points to a wiring fault or faulty sensor. Also check the sensor output voltage on the live values 2012 TDV8 Vogue (L322)

It doesnt sound like you are over-sooting.

If you can post:
A) Mileage
B) Inferred Soot
C) Number of demanded regens.
D) Type of driving.

I can help you eliminate sooting, and the root causes thereof as the problem, but as JayGee says it's more likely to be a wiring fault or a sensor. 2012 L322 4.4 TDV8 AB low mileage - a peach
1986 V8 Defender 90 County ex-Swiss Army - Red everything....

My preferred Independent: Roy Hardy. R & B AUTOS LTD, 20 Brook Road, Wimborne, Dorset, BH21 2BH (Ex LR Chief Technician)

Thanks for the offer! 👍
Mileage currently 102k
Soot level currently 18g. This has risen from less than 2g in only 40 miles of mixed rural driving but no warning light as yet.
Number of demanded regens 95. Car was a London car for about 5 (previous owner) who had 3 separate visits to garage to fix this.
Type of driving is normally rural with weekly motorway/dual carriageway runs. I thought my Amber DPF on Saturday was odd as I’ve done a lot of motorway miles (c.600) in the last 2 weeks with little else. On the day I’d been driving 2 hours over 50mph on mostly dual carriageways so my suspicion is that DPF is fine but something else not quite right.

My next step is to do the voltage tests as in WM properly. I’m getting about 0.75V at pressure sensor when ignition on and 0rpm, it goes up as it should on idle to about 0.8, but goes to 3V at 4000rpm so we’ll over the expected 1V. I need to check this again as didn’t hold revs for 7s to stabilise so will report back later when done.

Finally, I had my EGR valve changed by Glenrands recently and before I could get the vehicle back it was delayed as they were having problems with the boost pressure, which they subsequently sorted with a new vacuum control hose (LR076025). Therefore, I can only assume that this side of the system is ok, but not averse to going for high pressure smoke test if that’s the best way to rule anything in this area out. Andy

2010 4.4TDV8 Vogue SE in Santorini Black with Ivory interior
2017 Audi SQ5 3.0 V6T Quattro in Volcano Red
2001 Audi Allroad 2.5 TDI manual with low-range in Highland Green. Currently SORN whilst undergoing some serious restoration!

The number of demanded regens is very low for that mileage. If someone has reset the DPF in a GAP IID tool or similar and not cleaned or replaced the DPF then it would mess with the regeneration schedule. It's also low mileage for the age but not if it's been a city car for most of that and done the school runs it won't have been kind on a DPF system. What's your MPG / distance to empty when you have filled up? 2012 TDV8 Vogue (L322)

JayGee - I became aware that it was previously a city car a few months back when I contacted the garage where it had been taken and they very kindly sent me all of the invoices for servicing and other work over the 5 or so years they worked on it. They did a forced DPF regen at least twice, if not 3 times in that period. It was therefore no surprise when my EGR started failing and I was lucky to have that changed out under warranty. I also plan to have my DPF taken off and sent for a proper chemical cleaning and as a kind of ‘reset’ under my ownership. However, I don’t want to do that until I have ruled out all other possible failures in the system otherwise I’ll be treating the symptom and not the cause, risking me wasting the money as the DPF fills back up again. I’m confident that my driving style is unlikely to cause DPF problems if the system works as intended.

Anyway, to answer your question, on a recent 140 mil nighttime (so minimal traffic) motorway cruise I got 32mpg driving on cruise at 70mph pretty much the whole way (less 10 miles mixed driving off the motorway at each end of the journey) that figure is 100% accurate as it was a brim to brim fill and gps tracked for accurate mileage; I find my dashboard mpg to be quite optimistic so use an app to track).

On mixed driving with minimal extra-urban journeys I’m getting 23-25mpg using the same method. Andy

2010 4.4TDV8 Vogue SE in Santorini Black with Ivory interior
2017 Audi SQ5 3.0 V6T Quattro in Volcano Red
2001 Audi Allroad 2.5 TDI manual with low-range in Highland Green. Currently SORN whilst undergoing some serious restoration!

MPG is not outside the average. External DPF cleaning is to remove ash buildup not soot so if this is a problem it's tackling a possible cause and not a symptom and you can clear soot with regeneration drive cycles or forced methods via the GAP IID if needed. The amount of gunk in the intake doughnut and around the throttle plate would be a good indicator of what's lurking deeper in the engine as a result of excessive short city drive cycles.
Also the fault code indicates a wiring / sensor fail so this needs fixing / investigation before anything else. 2012 TDV8 Vogue (L322)

Curiosity led me to observing DPF control on mine today. Long drive on the M4 at 65mph and it started at 17g and gradually increased to so no passive regen is happening with the EGT around 300deg. Active regen kicked in at 19.7g , egr valve closed, egt went up gradually to 560deg and soot came down to just over 5g in about 5-10 mins. Successful regen counter didn’t change and demanded regen counter is over 1900 at 145k miles. Also observed egt at higher revs by dropping to 7th and 6th using the paddles and egt didn’t rise with revs. Rises when going up hill so confirms it’s load that controls egt. Never had a dpf light in a year and 17k + miles of driving. 2012 TDV8 Vogue (L322)

Latest update: it seems to be getting worse! But I now hopefully have some more clues.

I've now measured the exhaust pressure sensor V using the IID Tool and as per the WM instructions. It's about 0.73V with ignition on and 0rpm, then goes up to about 0.78V at idle; so both within parameters as expected as specified in the WM. However, when holding 4000rpm for at least 7s, it stabilises at approx 3.5V, which is well over the 1V that the WM says it should be. As per the WM's pinpoint tests and to rule this out, I am going to replace the exhaust pressure sensor and have already ordered a new genuine LR part to the tune of £80 for this. I also paid for the next day delivery as I want to get to the bottom of this ASAP so am planning to fit Fri PM after work.

However, I went for a drive earlier to take the dog for a walk in the hills, so narrow country roads for about 10 miles but with quite a few long straights so up to national limit a few times. Soot levels were rising quickly from the c.16g at the start of the drive and went over the threshold for active regen but it was not going to get a chance as not enough long stretches of road to keep the speed up. The rate of increase was alarming and I got the amber warning by the time I stopped. I then decided to take the longer route home so I could get onto the faster flowing roads and allow some chance for regen but I got the red warning and RP before I got to the main road as soot just kept rising so quickly. I triggered the forced regen using my IID Tool and it got it down to about 8g by the time I got home. All good, or so I thought...

A little later I needed to go to the supermarket for a few things. Its a nice 50-60mph road all the way but soot kept rising, again. Not as fast as on the back roads but it was still going up slowly over the 10 miles. Once finished in the shop, I thought I'd go for a blast on the dual carriageway to see what happened and as I entered the slip road I floored the car but it seemed quite sluggish, and there wasn't really any noticeable surge when the second turbo kicked in. The soot was still rising slowly and I got up to low 20g pretty quickly - bear in mind that I've only done about 10 miles since the forced regen that got it down to 8g.

Having thought the car felt sluggish on hard acceleration, when I got to a major roundabout after about 5 miles on the dual carriageway doing 70mph with soot still slowly rising I turned around and came back the other way but this time using command shift. When accelerating up to speed and with pedal to the floor I pushed it up to nearly 4000rpm in 2nd, changed to third and kept accelerating with full throttle and then I got Restricted Performance. I initially thought this would be a good thing as I hoped there would be another error code showing what might be a clue to the issue, but the only one showing was the same P244B-68 DPF Differential Pressure too high that I've been seeing since the weekend. Surely a dodgy exhaust pressure sensor isn't going to trigger RP, even when accelerating hard like that, is it? If you look at the error code in the DPF Testing document in the Exhaust section of the WM, it actually says to disregard P244B-68 unless another error code is showing.

One other thing to mention which may be a clue is that when lifting off the throttle, especially having been doing over 40-50mpg, the soot can rise by up to 1g in a matter of a few seconds during the coast after lifting off. As you can imagine, on a back country road or a busy A-road, lifting off is regular so it seems that this is when or why the soot levels could be rising most quickly. Either way, on anything other than dual carriageway/motorway, I doubt that I could drive for 30 miles without getting an amber/red DPF warning.

So, to summarise my planned next steps:
- I should be in a position to replace the exhaust pressure sensor on Fri with a new genuine LR Part. I will follow the calibration procedure as explained in the WM and hopefully this will rule out any further problems with this sensor and stop the P244B-68 code reoccurring.
- I have seen the earlier posts ref the 4 silicone hoses going into the doughnut. Ive already got the newer ones fitted (with two jubilees) but don't know if this was from new or, if not, when they were upgraded. However, to rule these out as an issue I have 4 replacement 70mm hoses coming from a decent supplier tomorrow and will also try and fit these on Fri pm to rule that out also. They were only £25 for all 4 so seems like an easy bit of preventative maintenance ad troubleshooting.
- If there is time, I'll clean out the MAF/MAP and throttle body, and maybe try the PTFE hack to see if I can improve the fit of the plastic elbow when refitting.

Can anyone suggest anything else obvious that I should look for or can check? I'm not averse to the high-pressure smoke test but figure I may as well clean and replace anything that is easy and good preventative maintenance before I do as something simple could fix this. Whilst I can't say for certain that it is oversooting, I contend that it would be near impossible to drive more that 20-30 miles at the moment on country roads before getting full dpf and no chance to regen, so I have to work on the assumption that the fill rate is well over what it should be. The fact that this has only started happening after doing 2 laps of the 4x4 course at Tixover, and when I've done many thousands of miles without a peep from the DPF beforehand, makes me assume that driving in low range and high revs on the 4x4 course, thus putting the engine under a lot of stress, has possibly broken something on the intake side of the engine hence the sudden rapid soot build up and the RP when really pushing the engine. My driving habits have not really changed before or after doing the 4x4 course so it seems the most likely culprit of the issue.

I would be most grateful for ideas or any other knowledge that might help me get to the bottom of this soon and so that I can start enjoying the vehicle again!  Andy

2010 4.4TDV8 Vogue SE in Santorini Black with Ivory interior
2017 Audi SQ5 3.0 V6T Quattro in Volcano Red
2001 Audi Allroad 2.5 TDI manual with low-range in Highland Green. Currently SORN whilst undergoing some serious restoration!

Latest update:
- I stripped and cleaned the seals/mating surfaces for the throttle body and plenum then reassembled with some gas PTFE on the throttle body to (hopefully) improve the seal.
- I replaced all 4 plenum short hoses with brand new aftermarket hose.
- I cleaned the sensor in the plenum
- I replaced the exhaust pressure sensor with a new genuine LR part and ‘calibrated’ as per WM instructions.

Results:
- Exhaust pressure sensor voltage still outside expected parameters as it’s measuring 3.5V when held at 4000rpm. Not sure why?
- Car still going into RP when I floor it and hold it through the gears. Is this likely an intake issue and effectively engine going into self preservation?
- I’m still getting P244B-68 error code. I’m also now getting P2458-66 DPF regeneration duration (bank 1) - signal has too many transitions/events. The WM says nothing helpful other than permanent regeneration. Can anyone enlighten me on this?
- Car did do an active regen and got the soot down to 0.15g before lowering the exhaust temps back to about 350C. However, soot went back up to about 10g within 10 miles, but at least I’ve now seen it do a regen which is good. I’ve got a long motorway journey planned for next weekend so a good opportunity to monitor the soot and exhaust temps so I can see if the DPF is working as it should or struggling to clear the soot as it builds.

Next steps:
- I think I need to find a garage that does a high pressure smoke test. Can anyone recommend anywhere near Faringdon on the Oxon/Wilts border?
- Is there anything else I should be doing at this stage before I start buying parts like a new plastic elbow to go on throttle body as preventative maintenance?

As always, sincerely grateful for any help and/or advice! TYIA Andy

2010 4.4TDV8 Vogue SE in Santorini Black with Ivory interior
2017 Audi SQ5 3.0 V6T Quattro in Volcano Red
2001 Audi Allroad 2.5 TDI manual with low-range in Highland Green. Currently SORN whilst undergoing some serious restoration!

I'd suspect the DPF now given high exhaust back pressure and rapid soot load. 2012 TDV8 Vogue (L322)