Diesel Cayenne and VW emission issue
01-15-2018, 05:08 PM
#5161
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Eskimo1, thanks for getting pre-fix data! Would complete the picture if someone would also get Pre & Post-fix dyno runs for both a 13/14 and a 15/16 CD.
We have a 2013 CD and got a pre dyno run - Here are our before -at the wheels- numbers run on a Dynojet with data normalized for temperature.
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Max Pwr______203.20___200.97_____202.42
Engine RPM___3.55______3.56______3.54
Max Trq_______354.82___356.82_____352.35
Engine RPM___2.46______2.44_______2.42
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Still not convinced to get the 'fix' - Would like to see numbers after the 'fix' - We do endurance off-road rally & Overlanding, can not afford to give up performance. One run last summer started at 3800' climbed to 8000' then descended to 4000' in less than one mile.
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Another potential issue for us is cold weather starts as in the -36F it got to in Yellowknife. Has anyone had the fix in the north, how has it started in sub-zero temps?
___________________________
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Eskimo1, thanks for getting pre-fix data! Would complete the picture if someone would also get Pre & Post-fix dyno runs for both a 13/14 and a 15/16 CD.
We have a 2013 CD and got a pre dyno run - Here are our before -at the wheels- numbers run on a Dynojet with data normalized for temperature.
.
Max Pwr______203.20___200.97_____202.42
Engine RPM___3.55______3.56______3.54
Max Trq_______354.82___356.82_____352.35
Engine RPM___2.46______2.44_______2.42
.
Still not convinced to get the 'fix' - Would like to see numbers after the 'fix' - We do endurance off-road rally & Overlanding, can not afford to give up performance. One run last summer started at 3800' climbed to 8000' then descended to 4000' in less than one mile.
.
Another potential issue for us is cold weather starts as in the -36F it got to in Yellowknife. Has anyone had the fix in the north, how has it started in sub-zero temps?
___________________________
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One thing I *did* notice - seems the cold *really* impacts fuel mileage. I bought my CD used a year ago, and it was a pretty mild winter last year - but I do not recall seeing a huge hit to mileage.
I seem to average 25 when it's super cold - I'm usually over 30. We had a warm week last week and mileage returned - back to low 30s. Not sure if that's a result of the "fix" or if that's normal for these though.
01-15-2018, 09:10 PM
#5162
Three Wheelin'
We've had a few weeks of very cold weather in Chicago - below zero for overnight lows, highs in the single digits. Sub-zero starts haven't been a problem.
One thing I *did* notice - seems the cold *really* impacts fuel mileage. I bought my CD used a year ago, and it was a pretty mild winter last year - but I do not recall seeing a huge hit to mileage.
I seem to average 25 when it's super cold - I'm usually over 30. We had a warm week last week and mileage returned - back to low 30s. Not sure if that's a result of the "fix" or if that's normal for these though.
One thing I *did* notice - seems the cold *really* impacts fuel mileage. I bought my CD used a year ago, and it was a pretty mild winter last year - but I do not recall seeing a huge hit to mileage.
I seem to average 25 when it's super cold - I'm usually over 30. We had a warm week last week and mileage returned - back to low 30s. Not sure if that's a result of the "fix" or if that's normal for these though.
I have not done the fix and I am also seeing lower mileage in the cold winter we have had this year. I guess that is to be expected in a diesel with no spark plug.
01-16-2018, 10:36 AM
#5163
Burning Brakes
Winter diesel has less BTU's per gallon, so that will impact things too.. It's similar to the hit you take with winter gasoline.
01-16-2018, 12:14 PM
#5164
Rennlist Member
Cold air should, in theory, increase power, since the air is denser. That's why we get intercooled turbos. I don't know if there's an optimal temp for diesel engines, though, so as far as I know, there could be a "too cold", too.
01-16-2018, 12:22 PM
#5165
Yeah usually 1-2 mpg loss over the winter, I'd expect.
But 5+?
If I had to make an assumption it would be extra regen's because of the super cold air and the cat not working as well?
But 5+?
If I had to make an assumption it would be extra regen's because of the super cold air and the cat not working as well?
01-16-2018, 10:53 PM
#5166
Rennlist Member
This is the cause, primarily. Anti-gel stuff reduces the amount of actual fuel in a gallon of stuff that you pump into your tank (resulting in the aforementioned less BTUs). I've found about 1-2 mpg in my Cummins diesel. Not sure, exactly, the impact to the CD yet, since up until this year, it was her DD. Now that I have one, too, I'll be able to check it closer.
Cold air should, in theory, increase power, since the air is denser. That's why we get intercooled turbos. I don't know if there's an optimal temp for diesel engines, though, so as far as I know, there could be a "too cold", too.
Cold air should, in theory, increase power, since the air is denser. That's why we get intercooled turbos. I don't know if there's an optimal temp for diesel engines, though, so as far as I know, there could be a "too cold", too.
01-17-2018, 12:30 PM
#5167
If so then... well... ok then.
Last year here in Chicago, the winter was exceptionally mild, and that was my first winter with the CD, so I may not have a good "baseline" for super cold weather.
01-17-2018, 03:28 PM
#5168
Rennlist Member
If I don't, the engine struggles to maintain operating temp and that may well kill mileage. I've not run extended times like that, although last year during our trip to CO, when it was -10ish driving through WY, the engine was struggling to hold it's normal temps. MPGs were down, but I thought it was because of the bike rack on the back and fully loaded vehicle. Even with warmer temps on the return trip, mileage was down. They were close, so I didn't think much of it, but maybe they were worse on the really cold legs.
01-18-2018, 11:11 AM
#5169
Burning Brakes
I was really impressed when I saw the radiator shutters, presumably it's for this very reason.. Speed warmup and keep Temps where the engineers want them. (helps mpg too)
01-18-2018, 06:47 PM
#5170
Banned
No, the burden of proof is on you; you claim to have empirical data. Post it. Prove it. I claim my impressions are not data based, but comparison based from "before". The burden of proof when you make wild *** claims is on the claimer... who claims to have the data to back up those claims. Post your hard empirical proof or join the rest of us in our comparison based, anecdotal data and stop claiming to know more than that.
Playing "I've got a secret" and am, therefore, smarter than the rest of you doesn't help this conversation. In fact, it's less helpful than those of us posting observations and anecdotal results to this thread.
As the saying goes: Put up or shut up.
Playing "I've got a secret" and am, therefore, smarter than the rest of you doesn't help this conversation. In fact, it's less helpful than those of us posting observations and anecdotal results to this thread.
As the saying goes: Put up or shut up.
I admit your 15'+ may be a bit different, but this discussion in inclusive to 13-16' years. If you want to sit over some Aslan, I may be in the area in May to discuss further the issue.
All I remember when doing my research in 2013 was that some automobile journalist were praising the smoothness of the VW 3.0 tdi, compared with others in the market. If I remember, Car and Driver had a comparison with the Jeep Grand Cherokee, the Mercedes M class (at that time?), and the BMW X5. I bet the other manufacturers were scratching their heads as to how VW/Audi was able to engineer the smoothness of the 3.0 tdi. Well, now we know.
Again, as you said, without empirical data, we can't tell wether the fix may affect the longevity of the engine (I assume that is what you are implying)
Again, as you said, without empirical data, we can't tell wether the fix may affect the longevity of the engine (I assume that is what you are implying)
Again, I'll ask who is the single greatest beneficiary of this "mess."?
I got Torque to work with my crappy old OBDII adapter, and was able to see EGT's, DPF pressure, boost, etc. Since my '16 is currently bone stock and un-fixed, this will be some good baselines.
Problem is, I don't have a frame of reference as to what "OK" EGT's are for this particular engine. My last diesel was a 12-valve Cummins, and with the EGT probe mounted several inches away from the (iron) head, the goal was to keep EGT's at or below 1200°. Brief spikes higher than that were OK (I pegged the 1600° gauge on a dyno pull), but for all-day towing, 1200° or below. Duramax guys (with their aluminum heads) were more liberal in their "safe" EGT's, normally saying something more like 1350-1400° is OK.
Doing a brake-launched 0-85mph pull in the CD yesterday, EGT's stayed at 1200-1300, and slowly climbed to a peak of ~1400° (Perhaps that's where the ECU starts de-fueling?). I've also realized why they don't give us a boost gauge - it's all over the place! Did see a peak of 37psi right at launch. As suspected with this small, responsive turbo, either mechanically or electronically, boost falls off at higher RPM. When I get a little time, I'll turn on data logging and get some of this in a CSV for those interested.
Problem is, I don't have a frame of reference as to what "OK" EGT's are for this particular engine. My last diesel was a 12-valve Cummins, and with the EGT probe mounted several inches away from the (iron) head, the goal was to keep EGT's at or below 1200°. Brief spikes higher than that were OK (I pegged the 1600° gauge on a dyno pull), but for all-day towing, 1200° or below. Duramax guys (with their aluminum heads) were more liberal in their "safe" EGT's, normally saying something more like 1350-1400° is OK.
Doing a brake-launched 0-85mph pull in the CD yesterday, EGT's stayed at 1200-1300, and slowly climbed to a peak of ~1400° (Perhaps that's where the ECU starts de-fueling?). I've also realized why they don't give us a boost gauge - it's all over the place! Did see a peak of 37psi right at launch. As suspected with this small, responsive turbo, either mechanically or electronically, boost falls off at higher RPM. When I get a little time, I'll turn on data logging and get some of this in a CSV for those interested.
01-18-2018, 07:03 PM
#5171
Banned
From what I’ve seen, the fix induces added stress on components that normally don’t like to be above 1300 degrees often. There are other measures induced in the software during regen vs driving up gradient (heavy loads) that come into play.
If the $10k is worth the warranty, than do it. I’m not denying it’s nice, but it’s in place for a specific reason and also a concession given from VW group for revising engine software for a purpose not originally intended.
If the $10k is worth the warranty, than do it. I’m not denying it’s nice, but it’s in place for a specific reason and also a concession given from VW group for revising engine software for a purpose not originally intended.
01-18-2018, 07:30 PM
#5172
From what I understand - you need 600C minimum for regen to be effective - and at 600C you still need significant time to truly clean out the brick (more than just a few minutes). You're trying to, quite literally, vaporize everything in there. So I'm not at all surprised to hear they're running closer to 900C to try to speed up the process... perhaps complete a full regen in 20-30 minutes vs an hour+. If the brick isn't clean it's effectiveness is reduced. How many people drive their cars long enough in a single drive to be able to incorporate a full regen? Probably not many.
This is likely why the .1's also got new catalysts.
IIRC the Powerstrokes run closer to 1000C and it still takes a solid 20-30 to clean the brick. I remember there were initial concerns - ranchers down in TX driving through dried out fields, leave their trucks idling and suddenly find a brush fire under their truck when the regen kicked off...
01-18-2018, 10:40 PM
#5173
Rennlist Member
Put up or shut up? Pathetic to be honest. Interesting that you've been touting no change in the way in which the new software is interacting with the hardware and somehow the burden of proof is on me. Get yourself a Diagnostic tool, related instruments, and investigate yourself or wait for some of known tuners like Malone or the guys that make the Bluebox (good luck as they're not stateside to receive the same software revision as us).
I admit your 15'+ may be a bit different, but this discussion in inclusive to 13-16' years. If you want to sit over some Aslan, I may be in the area in May to discuss further the issue.
Is not the advantage to the forum a discussion? I've been following this issue in far more detail than probably 99% of you. Have you seen any of the redacted emails exchanged by CARB and VW/Audi?
It's evident when with VCDS on a 14' Audi I've tested during the (Active) Regen process that is now around 1650 degrees without gradient. Mine isn't near that with similar driving. To say that there are less emissions with the fix via increased Regen's is one of the biggest lies yet. It doesn't work like that. Why do you think they now account for MPG's based off the original Maroney during normal emission (software cheat during rolling roads) testing and not what was actually happening? How unsual that a manufactures rated MPG's are so different than real world testing even after the revision that took place to window stickers not long ago. Take a look at how VW was using the software during their mid-models with/without Adblue. Much discussion with now regarding the EGR and components of the Turbo. The Regens cycles have increased and so has the temps now induced on said hardware.
Again, I'll ask who is the single greatest beneficiary of this "mess."?
Hmmm, now you're getting somewhere. Take a look with a PIWIS or similar VCDS on a fixed 14' or earlier model.
I admit your 15'+ may be a bit different, but this discussion in inclusive to 13-16' years. If you want to sit over some Aslan, I may be in the area in May to discuss further the issue.
Is not the advantage to the forum a discussion? I've been following this issue in far more detail than probably 99% of you. Have you seen any of the redacted emails exchanged by CARB and VW/Audi?
It's evident when with VCDS on a 14' Audi I've tested during the (Active) Regen process that is now around 1650 degrees without gradient. Mine isn't near that with similar driving. To say that there are less emissions with the fix via increased Regen's is one of the biggest lies yet. It doesn't work like that. Why do you think they now account for MPG's based off the original Maroney during normal emission (software cheat during rolling roads) testing and not what was actually happening? How unsual that a manufactures rated MPG's are so different than real world testing even after the revision that took place to window stickers not long ago. Take a look at how VW was using the software during their mid-models with/without Adblue. Much discussion with now regarding the EGR and components of the Turbo. The Regens cycles have increased and so has the temps now induced on said hardware.
Again, I'll ask who is the single greatest beneficiary of this "mess."?
Hmmm, now you're getting somewhere. Take a look with a PIWIS or similar VCDS on a fixed 14' or earlier model.
Either prove you've seen the data by sharing it and show us all to be the idiots you think we are or S**U.
If you have access to the data, share it for the benefit of the forums. Otherwise, no, it's not benefiting the forum for you to come in and claim to know more, have the proof and then just leave it at that, and that because we don't have that same data you claim to, we're somehow less intelligent, observant or aware of the issue.
Last edited by skiahh; 01-19-2018 at 02:47 AM.
01-18-2018, 11:44 PM
#5174
Rennlist Member
01-18-2018, 11:49 PM
#5175
Rennlist Member
You know, now that I think about it, in the truck, any time it's really cold, I put on a radiator cover to keep the engine temps up.
If I don't, the engine struggles to maintain operating temp and that may well kill mileage. I've not run extended times like that, although last year during our trip to CO, when it was -10ish driving through WY, the engine was struggling to hold it's normal temps. MPGs were down, but I thought it was because of the bike rack on the back and fully loaded vehicle. Even with warmer temps on the return trip, mileage was down. They were close, so I didn't think much of it, but maybe they were worse on the really cold legs.
If I don't, the engine struggles to maintain operating temp and that may well kill mileage. I've not run extended times like that, although last year during our trip to CO, when it was -10ish driving through WY, the engine was struggling to hold it's normal temps. MPGs were down, but I thought it was because of the bike rack on the back and fully loaded vehicle. Even with warmer temps on the return trip, mileage was down. They were close, so I didn't think much of it, but maybe they were worse on the really cold legs.