When i bought my 180 salesman said the new euro 6 may have prob with the adblue pump he may have been trying to get rid of his old 180 stock as was thinking 204
Hello all,
I stumbled across this site when searching if anyone else is wondering fluctuation and strangeness of T6 diesel fuel consumption.
I'm currently struggling with the issue because I also have a T6 with exceptionally high fuel consumption compared with a few other T6's, and late T5's. Besides normal diagnostics local VW service has checked a couple of traditional "hardware" things to eliminate obvious issues and all the available modifications have been implemented on the vehicle. Based on what I read in this thread it is obvious that I'm also challenged with similar problem as you Twoguns (and most likely quite many others) although I have had only once engine light on (this far) and that for different fault code. Interesting thing is that I have the same fault code "31103 - SCR NOx Catalyst Bank 1, P20EE 00 [039] - Efficiency too Low" sitting in my ECU but it hasn't turned on the light.
Currently I'm driving with a VCDS-package recording a bunch of engine parameters. And, thanks to the dealer, also verified quite a few of the measurements with their VW certified equipment. The dealer have also "offered" me (while investigating mine) opportunity to make measurements with different variants of 2.0TDI engines of T6 (and also T5's as I so requested) to verify that there are engines which work as expected, and unfortunately quite a few that do not. So, now I have been able to convince the dealer that mine and a few others up here definitely have a problem and a clear symptom and common for all of them is bad mileage. Through the dealer has been filed quite a few measurements of mine and of "good samples" for comparison and verification - the comment we received back this far was only: "interesting" (a month and a half ago).
To help sort this out, or actually just to collect "evidence", I would like ask you all who are interested to keep a diary of couple of things, and let us all know. Currently it seems that problematic vehicles have quite a fluctuation in their short period (50-150km) fuel consumption even on one continuous run. Unfortunate is that periods of good/bad mileage are relatively short - so during full tank they average out, and so the result you get is explained to be normal because of "cold weather, driving style, big car, etc."
See an example below. Even better would be if you could on your longer trip record and reset your MFD(1) mileage every 30-50 km (20-30 miles). The reason for the split is to isolate regeneration period and other ongoing "suspicious" activities. Anyways, any data is appreciated, on any engine/transmission, in any units miles/km, mpg(UK), liters/km. Also would be interesting if you could record "Oil change counter" before or after each trip. Especially interesting would be records from other engines than 110kW/150hp variants because that seems to be only way to prove that something is not right with these specific ones.
Diary:
Engine type, Power, Emission cert, Front wheel/4Motion, Manual 5 or 6 /DSG-transmission, Equipped with Webasto-engine/cabin heater.
CXFA, 110kW/150hp, EU6/SCR, 4-Motion, DSG, Webasto engine heater
Tank 1:
Distance driven/ Av. fuel cons. MFD1/ Av. speed MFD1/Outdoor temp/ Oil change counter/ load
28 miles, 55 mpg, 38mph, -5C, Oil change 8700 mi, light load <200kg, medium 500kg)
20 miles, 45 mpg, 45 mph, 0C, light load
17 miles, 35 mpg, 42 mph...
60 miles, 29 mpg, 48 mph...
etc..
About 10 runs should be sufficient to get impression of what might be going on...
Refueled XX litres, total distance driven YYY miles, Av. fuel consumption on MFD(2), Av. speed MFD(2), (then reset).
Although you might get biased I "reveal" that with "the good ones" the mileage on MFD(1) I get doing steady 70-90 kph (45-55 mph) is without any difficulties 51-56 mpg (UK gallons), outdoor temp around 0C, studded winter tyres. Of course the MFD(1) is quite optimistic but correcting the number by +9% (in my case) it matches what I get from the engine control unit and at tank fill up, too. Unfortunately it seems that MFD(2) is way more optimistic (20%) and has a lot more variation (9..32% per tank based on statistics of more than 25 fill ups). Also with "the good ones" regereration is a rare event (more than 450 km) but mine is doing about twice more often (250 km) at same conditions. With mine the mileage varies hugely 25...50mpg in same conditions (without regeneration going on).
If any of you with this variant (diesel 110kW/150hp) have a chance to run yours on dyno, I would be delighted to hear the results. Based on some preliminary "homemade" measurements I would be amazed if you would get torque/power even close to the spec. I'll definitely take mine and a "good one" to a dyno as soon as spring reaches us because the dyno won't accept studded tyres.
Thanks.
mmi
PS. I'm expecting to have ECU software updated in two weeks. The update was not yet available last Wednesday (5APR) when they changed DPF differential pressure sensor as part of latest campaign. Unfortunately that didn't change anything (has been one of recorded engine parameters so I was able to verify it right away). Anyways, my expectations are not very high based on what they announced about the update.
=================
EDITed in April-2021:
Eventually got to the bottom of the fluctuating fuel consumption.
www.t6forum.com
I stumbled across this site when searching if anyone else is wondering fluctuation and strangeness of T6 diesel fuel consumption.
I'm currently struggling with the issue because I also have a T6 with exceptionally high fuel consumption compared with a few other T6's, and late T5's. Besides normal diagnostics local VW service has checked a couple of traditional "hardware" things to eliminate obvious issues and all the available modifications have been implemented on the vehicle. Based on what I read in this thread it is obvious that I'm also challenged with similar problem as you Twoguns (and most likely quite many others) although I have had only once engine light on (this far) and that for different fault code. Interesting thing is that I have the same fault code "31103 - SCR NOx Catalyst Bank 1, P20EE 00 [039] - Efficiency too Low" sitting in my ECU but it hasn't turned on the light.
Currently I'm driving with a VCDS-package recording a bunch of engine parameters. And, thanks to the dealer, also verified quite a few of the measurements with their VW certified equipment. The dealer have also "offered" me (while investigating mine) opportunity to make measurements with different variants of 2.0TDI engines of T6 (and also T5's as I so requested) to verify that there are engines which work as expected, and unfortunately quite a few that do not. So, now I have been able to convince the dealer that mine and a few others up here definitely have a problem and a clear symptom and common for all of them is bad mileage. Through the dealer has been filed quite a few measurements of mine and of "good samples" for comparison and verification - the comment we received back this far was only: "interesting" (a month and a half ago).
To help sort this out, or actually just to collect "evidence", I would like ask you all who are interested to keep a diary of couple of things, and let us all know. Currently it seems that problematic vehicles have quite a fluctuation in their short period (50-150km) fuel consumption even on one continuous run. Unfortunate is that periods of good/bad mileage are relatively short - so during full tank they average out, and so the result you get is explained to be normal because of "cold weather, driving style, big car, etc."
See an example below. Even better would be if you could on your longer trip record and reset your MFD(1) mileage every 30-50 km (20-30 miles). The reason for the split is to isolate regeneration period and other ongoing "suspicious" activities. Anyways, any data is appreciated, on any engine/transmission, in any units miles/km, mpg(UK), liters/km. Also would be interesting if you could record "Oil change counter" before or after each trip. Especially interesting would be records from other engines than 110kW/150hp variants because that seems to be only way to prove that something is not right with these specific ones.
Diary:
Engine type, Power, Emission cert, Front wheel/4Motion, Manual 5 or 6 /DSG-transmission, Equipped with Webasto-engine/cabin heater.
CXFA, 110kW/150hp, EU6/SCR, 4-Motion, DSG, Webasto engine heater
Tank 1:
Distance driven/ Av. fuel cons. MFD1/ Av. speed MFD1/Outdoor temp/ Oil change counter/ load
28 miles, 55 mpg, 38mph, -5C, Oil change 8700 mi, light load <200kg, medium 500kg)
20 miles, 45 mpg, 45 mph, 0C, light load
17 miles, 35 mpg, 42 mph...
60 miles, 29 mpg, 48 mph...
etc..
About 10 runs should be sufficient to get impression of what might be going on...
Refueled XX litres, total distance driven YYY miles, Av. fuel consumption on MFD(2), Av. speed MFD(2), (then reset).
Although you might get biased I "reveal" that with "the good ones" the mileage on MFD(1) I get doing steady 70-90 kph (45-55 mph) is without any difficulties 51-56 mpg (UK gallons), outdoor temp around 0C, studded winter tyres. Of course the MFD(1) is quite optimistic but correcting the number by +9% (in my case) it matches what I get from the engine control unit and at tank fill up, too. Unfortunately it seems that MFD(2) is way more optimistic (20%) and has a lot more variation (9..32% per tank based on statistics of more than 25 fill ups). Also with "the good ones" regereration is a rare event (more than 450 km) but mine is doing about twice more often (250 km) at same conditions. With mine the mileage varies hugely 25...50mpg in same conditions (without regeneration going on).
If any of you with this variant (diesel 110kW/150hp) have a chance to run yours on dyno, I would be delighted to hear the results. Based on some preliminary "homemade" measurements I would be amazed if you would get torque/power even close to the spec. I'll definitely take mine and a "good one" to a dyno as soon as spring reaches us because the dyno won't accept studded tyres.
Thanks.
mmi
PS. I'm expecting to have ECU software updated in two weeks. The update was not yet available last Wednesday (5APR) when they changed DPF differential pressure sensor as part of latest campaign. Unfortunately that didn't change anything (has been one of recorded engine parameters so I was able to verify it right away). Anyways, my expectations are not very high based on what they announced about the update.
=================
EDITed in April-2021:
Eventually got to the bottom of the fluctuating fuel consumption.
[T6_measured] Fickle fuel consumption on MFD – encore
In March 2020 finally got the long-awaited ECU (Engine Control Unit) software update. Unfortunately it took a while to get a good chance to do some measurements to try to figure out what has been changed. So finally a few weeks back dusted the VCDS and collected all kind of intriguing data. The...
Last edited:
Update:- van in at main dealer to look at the warning light for NOx sensor. Arrived and the van already had a warranty job sheet printed out for the software update and they mentioned anyone booking their 150 in will receive this as a recall.
On a side note the light was reset 10 days ago by Vw assist and came back on after 100 miles strangely this time it went out while the vehicle was in motion, normally it only goes out on a restart of the engine, this was after the first failed attempt at uploading the software. I will update when the dealer calls later in the week.
On a side note the light was reset 10 days ago by Vw assist and came back on after 100 miles strangely this time it went out while the vehicle was in motion, normally it only goes out on a restart of the engine, this was after the first failed attempt at uploading the software. I will update when the dealer calls later in the week.
D Day today. Finally picking up the van from the dealers today after they replaced a Sensor and wiring loom toward the rear of the exhaust and carried out the "Campaign" work of, replacing the exhaust pressure sensor before the DPF and software update if relevant. They report that my software is already up to date from when it was built. (Picked mine up end of September) So not everyone will need a software update.
Will report back once I've picked it up and hopefully put more than 300Miles without a EML coming on.
Will report back once I've picked it up and hopefully put more than 300Miles without a EML coming on.
Fingers crossed!
Really hoping they've nailed it this time for you.
T6 Dave's Dad
Member
Good luck, sir
and I truly hope that all will now be well 
. If it isn't fixed there is going to be a lot of egg on face in VWCV though.
Unbelievable, no the EML hasn't come back on (only done 35miles)but I thought I'd check all my electronics of my conversion as they had to run the new wiring Loom up through the floor below the passenger seat only to find that the controller for the eberspacher can't detect the heater so I'm unable to turn the heater on!!!!! Thankfully I'm going to the converters tomorrow to finally replace the shit Kenwood unit for a Pioneer that everyone recommends so hopefully they will be able to work it out. Probably heavy handed gimp has cut or disconnected something.
Doesn't end there either!!!! Got home washed van as I haven't had it for the best part of a month and I didn't want the dealer to wash it and add Custom swirls to have a phone call from my VWCV Customer Care guy who was surprised that I had picked the van up today as the Factory had asked the dealer yesterday to check the EGR value for excess soot, they didn't!!!
So I went ape shit with the VWCV guy saying why have they ignored advice from the top guys at the factory, he agreed and could only apologise and said he would be having words with the dealership which is Sinclair Of Swansea (haven't named them up to now but now they deserve to be named and shamed). He tried to assure me that the work they have done so far could fix the problem and that the EGR check could of been just cautionary and that I could book it back in. I told him yet more time wasted and fuel so I told him I'll drive it for a couple of hundred miles to see if the EML comes back on as it could be going back down anyway if it does.
Can't believe they didn't check the EGR as it would of been more money for them and it could of meant the back of me going there giving them grief. Maybe they have more than enough work with these vans.
Doesn't end there either!!!! Got home washed van as I haven't had it for the best part of a month and I didn't want the dealer to wash it and add Custom swirls to have a phone call from my VWCV Customer Care guy who was surprised that I had picked the van up today as the Factory had asked the dealer yesterday to check the EGR value for excess soot, they didn't!!!
So I went ape shit with the VWCV guy saying why have they ignored advice from the top guys at the factory, he agreed and could only apologise and said he would be having words with the dealership which is Sinclair Of Swansea (haven't named them up to now but now they deserve to be named and shamed). He tried to assure me that the work they have done so far could fix the problem and that the EGR check could of been just cautionary and that I could book it back in. I told him yet more time wasted and fuel so I told him I'll drive it for a couple of hundred miles to see if the EML comes back on as it could be going back down anyway if it does.
Can't believe they didn't check the EGR as it would of been more money for them and it could of meant the back of me going there giving them grief. Maybe they have more than enough work with these vans.
One word sums them up Numpties
Auto stop start won't be any good at detecting a Regen. There are many reasons why itb isn't always on. Battery voltage is usually the main culprit as the alternator smart charges. So stop start won't activate to charge the battery.
2 Regen's per tank full which in my van is 3 times a week. Pretty normal for modern diesels.
T6 Dave's Dad
Member
T6 Dave's Dad
Member
How do you know, I have not got clue if mine had done a regen, other that one day the fan stayed on for a while when I got home
