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BMW Diesel Owners / Enthusiasts
Do you own a diesel powered BMW? Maybe a 335d or a BMW x35d? Come and talk about what makes your car great!

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  #226  
Old 05-31-2012, 03:09 PM
Snipe656 Snipe656 is offline
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Quote:
Originally Posted by Snipe656 View Post
Just google "will DEF improve fuel economy" and you will get a number of hits claiming around a 4% increase by using it. I'd not be surprised if they are biased reasons though.
Or google on why Passat TDI gets better economy than Jetta. There are a number of posts about it on the TDi forums. Sounds like basically since DEF allows Nox reduction that they can tune the motor differently and rely on the DEF to reduce that. Where as on the Jetta they basically rely on the burn off process more so and fuel is used for that process. But unless I am misreading things it sounds like they both still have a burn off process but it happens less often on the Passat due to able to tune the engine differently for overall emissions. Or maybe I am reading wrong on the burn off process have squat to do with it either way. I only skimmed things before posting but it seems pretty definite that by adding DEF to the cars it allows for better fuel economy.
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Last edited by Snipe656; 05-31-2012 at 03:18 PM.
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  #227  
Old 06-01-2012, 10:12 AM
clippernation clippernation is offline
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Mein Auto: 2012 F30
Brought mine in on Weds morning, got it back last night. Apparently they ran into some kinda of glitch when first uploading the new software and has to install the 'bus' as it was missing, according to the papers at least. I told them about the SIB for the A/C belt but they said they couldn't find it in the system. No F30 loaner too
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  #228  
Old 06-01-2012, 02:39 PM
Penguin Penguin is offline
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Quote:
Originally Posted by Snipe656 View Post
But unless I am misreading things it sounds like they both still have a burn off process but it happens less often on the Passat due to able to tune the engine differently for overall emissions.
The burn-off is for the particulate filter, to keep the particulate count down. DEF does not impact particulate "pollution," it is primarily to keep the NOx numbers down. So you are correct, a DEF system will not impact the need for a periodic "burn off."
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  #229  
Old 06-01-2012, 03:18 PM
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rmorin49 rmorin49 is offline
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On my commute today, car seemed peppier but the loaner was a 328i so this is the likely explanation.
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  #230  
Old 06-01-2012, 04:26 PM
Snipe656 Snipe656 is offline
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Quote:
Originally Posted by Penguin View Post
The burn-off is for the particulate filter, to keep the particulate count down. DEF does not impact particulate "pollution," it is primarily to keep the NOx numbers down. So you are correct, a DEF system will not impact the need for a periodic "burn off."
But in my quote I was not saying that it will not impact the need for periodic burn offs, all along I have been trying to say that having DEF put into the vehicles has allowed for less regens unless I was just misunderstanding what I skimmed originally. Google "does def allow for less dpf regeneration" and there seems to be plenty of things posted explaining how the usage of DEF does in fact allow for the entire combination of the vehicle to not need to do DPF regens as often. Such as this link:

http://www.factsaboutscr.com/perform...operation.aspx

Which states within there:

Quote:
Moreover, the higher NOx levels out of engine do not only result in higher combustion temperatures but also in lower levels of particulate matter going into the DPF. This means that the DPF needs to be regenerated less frequently, thereby needing less fuel.
Or this link:

http://www.demanddetroit.com/performance/emissions.aspx

Which states within there:

Quote:
This allows our engines to perform at optimal combustion ranges to provide peak power and reduce heat rejection on many of the internal engine components. Another major contributing factor to this improvement is that the engine's diesel particulate filter (DPF) extends its regeneration intervals
and so on ....
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  #231  
Old 06-01-2012, 10:13 PM
tol4o tol4o is offline
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Theoretically, if you open pipe the 35d engine and delete/bypass all of the emission systems /nothing after the turbos - no DPF, no SRC no DEF/, what % gain in the performance and MPG do you think will occur? At the same time - how contaminated will be the exhaust gases?
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Last edited by tol4o; 06-01-2012 at 10:22 PM.
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  #232  
Old 06-02-2012, 05:11 AM
Snipe656 Snipe656 is offline
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Quote:
Originally Posted by tol4o View Post
Theoretically, if you open pipe the 35d engine and delete/bypass all of the emission systems /nothing after the turbos - no DPF, no SRC no DEF/, what % gain in the performance and MPG do you think will occur? At the same time - how contaminated will be the exhaust gases?
While not a 100% match to a US car, you might be able to find the numbers for this via the Euro boards. I know a video was posted of a car that had no DPF and I believe no SRC then they already lack DEF. Maybe the person mentioned any mpg difference in forum postings. I do believe they mentioned no real gain other than a lot of soot for the lack of a DPF.
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  #233  
Old 06-03-2012, 07:14 PM
boooomer boooomer is offline
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Originally Posted by floydarogers View Post
One thing that definitely is lost due to the re-programming is the transmission adaptations. Those adaptations have a significant affect on mileage (think DS vs. D mode). I've noted that the default on my car is more similar to DS than it was before - shifting at higher revs.
I normally use the manual shifter & force upshifts because I think the transmission holds the gear too long. But I'm afraid that in manual mode it won't reprogram. So after the recall I've been leaving it auto, driving very gently to encourage faster upshifts at lower revs.

Does anyone know how long or how many miles it takes for the tranny to reprogram itself?
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  #234  
Old 06-03-2012, 08:46 PM
tol4o tol4o is offline
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i didn't even know that the transmission is adapting the shifting depending on how you drive the car. Is that for real?
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  #235  
Old 06-03-2012, 08:58 PM
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bayoucity bayoucity is offline
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Originally Posted by tol4o View Post
i didn't even know that the transmission is adapting the shifting depending on how you drive the car. Is that for real?
I'm unsure either. Other than my milage decrease after the EGR fixed, I also realize the shifting from 1st to 2nd is much smoother especially stomping gas pedal from green light.
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  #236  
Old 06-03-2012, 10:51 PM
nok nok is offline
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I had the recall done last Tuesday. I had noticed some roughness in the engine while the car warmed up prior to the update. I have a fairly steep hill if I take a right out of my nieghborhood and the car wouldn't miss or anything, but it was sort of surging. I don't think it always did this, but it's gone since the recall. The car seems faster, too, with about a 3% drop in indicated MPG. Worth it, in my opinion.
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  #237  
Old 06-04-2012, 03:55 AM
Snipe656 Snipe656 is offline
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Quote:
Originally Posted by tol4o View Post
i didn't even know that the transmission is adapting the shifting depending on how you drive the car. Is that for real?
Yes, they are adaptive like a lot of newer cars these days. What I do not know offhand though is if they constantly are adapting or only adapt after a reset. For example if i remember correctly my truck only adapts for a short while after a reset then never again.
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  #238  
Old 06-04-2012, 06:02 AM
TDIwyse TDIwyse is offline
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Originally Posted by TDIwyse View Post
Took a trip to Chicago area this morning. Filled up last night to get a fresh baseline for trip. ~250 mls. Rain for 1/2 of the drive and ~15mph headwind for all of it. ~50F for temps. Mostly 70-75 mph. Indicated mpg's were 34.5 and hand calculated was 37.5 mpg's. This is the largest % difference between hand calculated and computer indicated I've ever measured (spreadsheet has every fillup and tracks hand calc vs indicated). Will keep tracking to see if it comes back inline. But 37.5 for these conditions seems to be about what I would've expected before the recall. So I'm not sure yet what to think of the impact to mpg's . . . just trying to shed some data on the situation but I might have muddied the waters more.
After several hundred miles and multiple fillups my indicated vs hand calculated numbers are back in agreement, and the car is returning at least as good of mpg's as before.

There's a fantastic pdf document referenced around here (http://www.bimmerfest.com/forums/sho...50&postcount=4) that goes into the adaptations the computer does. Lots and lots of adaptations...
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  #239  
Old 06-08-2012, 07:10 AM
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Axel61 Axel61 is offline
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Ok amigos I took my car to BMW yesterday, I sat with the INCOHERENT/IGNORANT and Incompetent SA, I described the recall he didnt knwo either the AC issue either, I showed him a picture of the error codes and he TRIED to give me a lecture, I shut him up on this cause I told him this thing lights up today and tomorrow its gone. Anyway, he said that Puerto Rican laws protected him of giving me a vehicle I told him I was late for my appointment that i would address this later. I called him at 3:30 and he told the car had NOT been thru DIAGNOSTICs i said WTF 6 hours later and NOTHING done!!! I blew my fuse professinally and he said he still could not give a car i told him I will bite the bullet today but I better have A CAR tomorrow he said he warned me I blew a bigger fuse and went a little OFF on him and told him Id bet there in 20 minutes to p/u my house keys. Needless to say he calls me half way my trip to inform me that the EGR is DEFECTIVE and to p/u my car since they have to order the parts. I got there and he WAS NOWHERE in site. Im planning in speaking to the general manager and have me voiced out. Luckily he is a friend of my mechanic otherwise I still would be out of a car toady!!!!
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  #240  
Old 06-08-2012, 07:19 AM
BrianNC81 BrianNC81 is offline
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They changed out the DEF mixer and SCR Catalyst on my car. The EGR was replaced a few months back with the newer designed unit on the last round in the shop due to carbon buildup.

I've noticed a very strong burning smell (worse than DPF burn off) since they changed out the SCR catalyst. I'm thinking its due to the new part being "burned in" so will give it some time before taking it in to be looked at.

During the week the car was at the dealership (not all parts were on hand) they gave me a 2012 335i coupe. It felt a little sluggish in normal driving compared to the D. You simply can't beat the torque of the D.
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  #241  
Old 06-08-2012, 07:22 AM
Snipe656 Snipe656 is offline
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Originally Posted by BrianNC81 View Post
They changed out the DEF mixer and SCR Catalyst on my car. The EGR was replaced a few months back with the newer designed unit on the last round in the shop due to carbon buildup.
I have a feeling I might get lucky enough to have all three replaced. But thus far I have had two failed attempts on my part to try and drop off the car. If I keep this up then it might need rear brakes by the time I get there.
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  #242  
Old 06-08-2012, 07:30 AM
tol4o tol4o is offline
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Originally Posted by BrianNC81 View Post
During the week the car was at the dealership (not all parts were on hand) they gave me a 2012 335i coupe. It felt a little sluggish in normal driving compared to the D. You simply can't beat the torque of the D.
Picked up our 2011 X5D from the re-call service 2 days ago. Will report about that later when I have more time.
Anyway they gave us 2011 328xi as a loaner. Man that thing was so sluggish compared to the X5 diesel and my M3. Basically at 2000 rpm you press the accelerator without changing the gears and literally nothing happens! You have to press the pedal harder to get some crazy downshifting to get the rpm to 4-5k to feel any push of acceleration. The lack of torque is so obvious! Don't even wanna talk about the fuel economy. For 30 miles city driving I re-topped the tank with 2.5 gallons gas!!!
Thank you but am stuck with diesels and M3 cars
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Last edited by tol4o; 06-08-2012 at 07:32 AM.
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  #243  
Old 06-08-2012, 07:46 AM
BrianNC81 BrianNC81 is offline
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Originally Posted by tol4o View Post
Picked up our 2011 X5D from the re-call service 2 days ago. Will report about that later when I have more time.
Anyway they gave us 2011 328xi as a loaner. Man that thing was so sluggish compared to the X5 diesel and my M3. Basically at 2000 rpm you press the accelerator without changing the gears and literally nothing happens! You have to press the pedal harder to get some crazy downshifting to get the rpm to 4-5k to feel any push of acceleration. The lack of torque is so obvious! Don't even wanna talk about the fuel economy. For 30 miles city driving I re-topped the tank with 2.5 gallons gas!!!
Thank you but am stuck with diesels and M3 cars
The 335i with the twin turbo was not as bad as you are describing with the 328. It did pull at lower RPM's but not nearly as hard as the D. To really get it going it had to downshift and rev over 4000 RPM. 300LB torque vs 425 in the D .. The D had 42% more torque to put it in perspective. Average about 16MPG in the 335I where in the same conditions I get 25mpg in the D.

The 328's 6cyl non-turbo is only able to muster up 200lb of torque at 2700 RPM
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  #244  
Old 06-08-2012, 09:10 AM
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Flyingman Flyingman is offline
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Quote:
Originally Posted by Axel61 View Post
Ok amigos I took my car to BMW yesterday, I sat with the INCOHERENT/IGNORANT and Incompetent SA, I described the recall he didnt knwo either the AC issue either, I showed him a picture of the error codes and he TRIED to give me a lecture, I shut him up on this cause I told him this thing lights up today and tomorrow its gone. Anyway, he said that Puerto Rican laws protected him of giving me a vehicle I told him I was late for my appointment that i would address this later. I called him at 3:30 and he told the car had NOT been thru DIAGNOSTICs i said WTF 6 hours later and NOTHING done!!! I blew my fuse professinally and he said he still could not give a car i told him I will bite the bullet today but I better have A CAR tomorrow he said he warned me I blew a bigger fuse and went a little OFF on him and told him Id bet there in 20 minutes to p/u my house keys. Needless to say he calls me half way my trip to inform me that the EGR is DEFECTIVE and to p/u my car since they have to order the parts. I got there and he WAS NOWHERE in site. Im planning in speaking to the general manager and have me voiced out. Luckily he is a friend of my mechanic otherwise I still would be out of a car toady!!!!
Of course this was all in Espanol!
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  #245  
Old 06-08-2012, 09:40 AM
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Axel61 Axel61 is offline
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I almost went SPANGLISH on his ASS! Thats how mad he got me, I sent an email to the General Manager earlier today will keep you all posted.
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  #246  
Old 06-10-2012, 10:21 AM
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bayoucity bayoucity is offline
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Originally Posted by Axel61 View Post
I almost went SPANGLISH on his ASS! Thats how mad he got me, I sent an email to the General Manager earlier today will keep you all posted.
Hola amigo ! Keep us updated! BTW, I learn a new phase from you :"I blew my fuse professinally" which is what you do when you are dealing with German. Most of the time, you need to blow a bigger fuse with boricuas. Just saying...
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  #247  
Old 06-11-2012, 05:10 AM
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Axel61 Axel61 is offline
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@Bayoucity eso es ceirto!! Here is the emai I sent the general manger and he as of yet has not responded:

CAMPAIGN NUMBER: 11E-A03 y SIB 64 08 11 regarding the belt



Dear Mr. Rosa, I write to you this email since I understand you are a very busy man managing AUTOGERMANA of Puerto Rico. I had the unpleasant experience yesterday to leave my car at your shop facilities in Guaynabo. I had made and appointment for which it was to my belief that the above campaign numbers were being addressed and parts were on hand. Needless to say, I had Mr. Carmona attend me and from the beginning we did not see eye to eye on this matter. I would be more than glad to speak to you about this encounter at any given time, which by the way was very distasteful for me and makes me wonder where has Customer Service gone? Fortunately, I happened to befriend Buru (for many years) whom happened to speak to you earlier yesterday.

I am a proud owner of a 335d and previous owner of an 02 MCS for which Buru made many fixes. So I can gladly say I have been a BMW owner for over 10 years, and make no mistake in upcoming years also! Situations like this can detract many clients and include myself. I hope we can convey in the future and settle this in an appropriate manner. A whole lot of people in some BMW forums are watching this Campaign issue closely and would eventually be detrimental for future buyers of regular or Diesel BMWs. Any questions feel free to respond to either this email and/or at axelhernandez61@yahoo.com or my cellular numero 787-459-4518. Gracias!!
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  #248  
Old 06-12-2012, 05:08 PM
dc_ian dc_ian is offline
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Maybe the emissions recall is a good thing..

http://www.reuters.com/article/2012/...8HCL3I20120612
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  #249  
Old 06-12-2012, 05:46 PM
Snipe656 Snipe656 is offline
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I saw that this morning. Life would be easer if we just got a list of the things that do NOT cause cancer. I'd imagine I would be a really short list.
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  #250  
Old 06-13-2012, 03:49 AM
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Axel61 Axel61 is offline
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I guess we are screwed on this, anoher thing to Blame cancer on, WTF!!

Last edited by Axel61; 06-13-2012 at 03:50 AM. Reason: correct words
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