DCT fuel economy Manual Vs Auto

Wads · 02-18-2009, 07:58 AM

Apologies if this has been covered before, I've searched without much luck (mods please close if it has been covered).

Basically what are people finding in differences in fuel economy between D and S modes?

My E93 M3 DCT is my first auto and I had assumed that using it in D modes would give the best MPG...... on my commute to work I would generally leave it in D2 and use cruise control on a few sections of 40mph road, with a few full on blats to redline per day...... I almost always ended up with 15.8mpg

With the second gear downchange pause pissing me off more and more I switched to driving exclusively in S5 about 6 fuel fill ups ago...... I'm now averaging 16.5mpg..... in manual mode I'm generally holding lower gears for longer and also having more fun.

Is it usual to find S modes giving better MPG than D?????

mkoesel · 02-18-2009, 08:27 AM

You know, one thing that could be happening is the transmission is actually not picking the best gear and thus is straining to keep the car's at 40mph with the cruise on. If the engine bogs too much, it will probably waste a lot of fuel. Do you have a lot of hills? Because the effect will be even moreso in that case. When in manual mode, you are probably more apt to select a lower gear when appropriate, thus keeping the engine from over working. Just a thought.

Wads · 02-18-2009, 08:32 AM

Quote:

Originally Posted by mkoesel

You know, one thing that could be happening is the transmission is actually not picking the best gear and thus is straining to keep the car's at 40mph with the cruise on. If the engine bogs too much, it will probably waste a lot of fuel. Do you have a lot of hills? Because the effect will be even moreso in that case. When in manual mode, you are probably more apt to select a lower gear when appropriate, thus keeping the engine from over working. Just a thought.

I suspect thats the case as D modes always seem to pick a higher gear than I would and changes up earlier as well....... my drive is mainly flat so hills don't make much difference. Also as far as the engine bogging it never changes down as quickly as I'd expect when wanting a boost of speed.

I'd be interested to hear if others find the same difference between D and S

footie · 02-18-2009, 08:57 AM

I was depressed getting only 17.8mpg but Wads figures have cheered me up.

Wads · 02-18-2009, 09:02 AM

Quote:

Originally Posted by footie

I was depressed getting only 17.8mpg but Wads figures have cheered me up.

Yep the only time I got above 17 was on the drive home from the dealer around the M25 where I saw 25mpg by the time I got home. The bad figures I usually get are more due to heavy traffic than a heavy right foot as when I do get the chance for a blast in the country the MPG generally goes up to the heady heights of 18!

graider · 02-18-2009, 02:18 PM

any one know how to convert 11L/100km to mpg?

Jimmer · 02-18-2009, 02:26 PM

Quote:

Originally Posted by graider

any one know how to convert 11L/100km to mpg?

Your cars computer can do it. In the menu I believe (not at my car) in config. I go back and forth mpg/litres , mph/km quite a bit.

Big Windy · 02-18-2009, 02:27 PM

Quote:

Originally Posted by graider

any one know how to convert 11L/100km to mpg?

google: "11L/100km to mpg"

vioala!

http://www.google.com/search?client=...UTF-8&oe=UTF-8

C17MooseDriver · 02-18-2009, 02:30 PM

Seems like there's not much difference in MPG between the 6MT and DCT. I've been getting about 16.5 to 18 MPG, mostly dependent on the amount of highway driving.

maaicher · 02-18-2009, 05:57 PM

I wish i got 17...i get 15.2 ish all the time...or is the number in the dash just wrong and i should calculate it myself every time i fill up?

!Xoible · 02-18-2009, 06:19 PM

i'd save a lot on gas if i got DCT. coz i wont drive the car due to lack of interest

335 S · 02-18-2009, 06:46 PM

Quote:

Originally Posted by maaicher

I wish i got 17...i get 15.2 ish all the time...or is the number in the dash just wrong and i should calculate it myself every time i fill up?

OH. MY. GOD. You're, like, looking for like, 1.8 miles per gallon? Reset the bozometer, cuz you just led this fine forum into the pantheon of teenage whingebagdom. I too feel that an additional 1.8 mpg will bring the seven sisters to their knees. Don't know who the seven sisters are? Ask your parents, and remember to eat your vegetables.

lincoln · 02-18-2009, 07:02 PM

Quote:

Originally Posted by 335 S

OH. MY. GOD. You're, like, looking for like, 1.8 miles per gallon? Reset the bozometer, cuz you just led this fine forum into the pantheon of teenage whingebagdom. I too feel that an additional 1.8 mpg will bring the seven sisters to their knees. Don't know who the seven sisters are? Ask your parents, and remember to eat your vegetables.

jml · 02-18-2009, 07:58 PM

Quote:

Originally Posted by 335 S

OH. MY. GOD. You're, like, looking for like, 1.8 miles per gallon? Reset the bozometer, cuz you just led this fine forum into the pantheon of teenage whingebagdom. I too feel that an additional 1.8 mpg will bring the seven sisters to their knees. Don't know who the seven sisters are? Ask your parents, and remember to eat your vegetables.

priceless post

icemang17 · 02-19-2009, 12:17 AM

For what its worth....my E92 coupe with DCT is averaging right at 17.2mpg for the last couple thousand miles.... including my short daily work commute in town and a bit of freeway every week.....

Wolf-e92 · 02-19-2009, 08:20 AM

Averaging 18.8 over 7500 miles with a mix of D and S but I drive 75 miles each way to work 3 times a week. It's all highway but a lot of times stop and go traffic.

Whenever I'm in S, it's with my M mode settings S5, M Dynamic, Sport. In D, I use D3.

keanu1 · 02-19-2009, 09:43 AM

Quote:

Originally Posted by graider

any one know how to convert 11L/100km to mpg?

11l/100km it's incredibile good!!

graider · 02-19-2009, 11:26 AM

Quote:

Originally Posted by keanu1

11l/100km it's incredibile good!!

it is a e46 m3 though, lol

Surprisingly, my car is pretty good on gas. If I drive like a grandma, it will be like 9.6L/100km. 11L/100km is when I redline throughout the day and drive spiritually.

DevJ · 02-19-2009, 03:29 PM

I'm getting 14.1 mpg...lol

Donghai · 02-20-2009, 11:46 AM

i got 11.3 mpg .... some advice plz..

AckM3 · 02-20-2009, 02:02 PM

Sounds about right, I used to avegrage 16.5 in D2, but lately I've been driving carefully in S3, avoiding 7th except on the freeway, and getting I'm 17.2mpg

footie · 02-20-2009, 04:11 PM

I mistakenly tripped the computer while entering the town and got the shock of my life. 7mpg was all I was getting, admittedly the traffic was barely moving but thank god most of my trips are out of town.

02-18-2009, 07:58 AM	#1
Wads Second Lieutenant 16 Rep 257 Posts Drives: E93 M3 & Tuned Focus ST Join Date: Feb 2008 Location: UK iTrader: (0) Garage List 2008 E93 M3 V8 [0.00] 2002 Honda S2000 [0.00] 1995 Suzuki Cappuccino [0.00] 2005 Boxster S [0.00] 2007 Ford Focus ST [0.00]	DCT fuel economy Manual Vs Auto Apologies if this has been covered before, I've searched without much luck (mods please close if it has been covered). Basically what are people finding in differences in fuel economy between D and S modes? My E93 M3 DCT is my first auto and I had assumed that using it in D modes would give the best MPG...... on my commute to work I would generally leave it in D2 and use cruise control on a few sections of 40mph road, with a few full on blats to redline per day...... I almost always ended up with 15.8mpg With the second gear downchange pause pissing me off more and more I switched to driving exclusively in S5 about 6 fuel fill ups ago...... I'm now averaging 16.5mpg..... in manual mode I'm generally holding lower gears for longer and also having more fun. Is it usual to find S modes giving better MPG than D????? __________________ E93 ///M3 M-DCT Testing soon: Lambo LP670 SV and Ferrari 430 Scuderia
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02-18-2009, 08:27 AM	#2
mkoesel Moderator 7515 Rep 19,368 Posts Drives: No BMW for now Join Date: Jun 2006 Location: Canton, MI iTrader: (1)	You know, one thing that could be happening is the transmission is actually not picking the best gear and thus is straining to keep the car's at 40mph with the cruise on. If the engine bogs too much, it will probably waste a lot of fuel. Do you have a lot of hills? Because the effect will be even moreso in that case. When in manual mode, you are probably more apt to select a lower gear when appropriate, thus keeping the engine from over working. Just a thought.
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02-18-2009, 08:57 AM	#4
footie Major General 1122 Rep 8,017 Posts Drives: i5M60 Join Date: Oct 2007 Location: No where fast iTrader: (0) Garage List 2024 BMW i5M60 [0.00] 2022 BMW i4M50 [0.00] 2020 BMW M5 Competi ... [0.00] 2008 E92 M3 [0.00]	I was depressed getting only 17.8mpg but Wads figures have cheered me up.
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02-18-2009, 02:18 PM	#6
graider Colonel 35 Rep 2,406 Posts Drives: py/kiwi e46 m3 Join Date: Aug 2007 Location: toronto iTrader: (0)	any one know how to convert 11L/100km to mpg?
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02-18-2009, 02:30 PM	#9
C17MooseDriver Captain 20 Rep 878 Posts Drives: E92 AW M3 6MT Join Date: Jul 2008 Location: San Antonio, TX iTrader: (0)	Seems like there's not much difference in MPG between the 6MT and DCT. I've been getting about 16.5 to 18 MPG, mostly dependent on the amount of highway driving. __________________
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02-18-2009, 05:57 PM	#10
maaicher Captain 62 Rep 791 Posts Drives: 2008 BMW M3 Join Date: Nov 2008 Location: San Diego, CA iTrader: (10)	I wish i got 17...i get 15.2 ish all the time...or is the number in the dash just wrong and i should calculate it myself every time i fill up? __________________ SOLD Current 2008 Space Grey E92 M3 * JRZ RS Pro * TE37SL * AP Racing * Sparco Evo * Akrapovic Slip On * Studio RSR Cage * SOLD 2003.5 E46 M3 * Apex ARC8 * MCS 2-Way * Stop-Tech C43 * Recaro Profi XL * SOLD 2008 Jet Black E92 M3 * HRE C20 19in Wheels * KW Clubsport * Huper Ceramic Tint * Stop-Tech Trophy BBK * Gintani SC & Gintani Custom Exhaust * Vertice Front Bumper * Arkym Diffuser *
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02-18-2009, 06:19 PM	#11
!Xoible Banned 837 Rep 46,029 Posts Drives: .... Join Date: Nov 2006 Location: . iTrader: (4) Garage List 2008 M3 [4.00] 2007 335i [9.00] 2008 528i [8.00] 2006 Infiniti - G35 ... [8.00]	i'd save a lot on gas if i got DCT. coz i wont drive the car due to lack of interest
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02-19-2009, 12:17 AM	#15
icemang17 Captain 41 Rep 644 Posts Drives: 2008 E92 M3 DCT Join Date: May 2008 Location: Stockton CA iTrader: (0)	For what its worth....my E92 coupe with DCT is averaging right at 17.2mpg for the last couple thousand miles.... including my short daily work commute in town and a bit of freeway every week..... __________________ Brian 2008 E92 M3, MR, DCT, extended BB leather, loaded! 1988 Porsche 928S4, Guards red/Champagne leather 1989 Porsche 928S4 track beast!!!
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02-19-2009, 08:20 AM	#16
Wolf-e92 Private 2 Rep 71 Posts Drives: M3 Join Date: Apr 2008 Location: Here & There iTrader: (0)	Averaging 18.8 over 7500 miles with a mix of D and S but I drive 75 miles each way to work 3 times a week. It's all highway but a lot of times stop and go traffic. Whenever I'm in S, it's with my M mode settings S5, M Dynamic, Sport. In D, I use D3.
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02-19-2009, 03:29 PM	#19
DevJ Colonel 154 Rep 2,736 Posts Drives: R8 V10+/YMB M4 Join Date: Nov 2007 Location: Tulsa, OK iTrader: (1)	I'm getting 14.1 mpg...lol __________________ ‘23 RRS First Edition '22 X7 M50i '18 R8 V10+ http://www.bimmerpost.com/forums/attachment.php?attachmentid=133578&d=1204654487[/IMG]
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02-20-2009, 11:46 AM	#20
Donghai Private 10 Rep 95 Posts Drives: 2008 E92 M3 Join Date: Jan 2009 Location: NY iTrader: (1)	i got 11.3 mpg .... some advice plz..
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02-20-2009, 02:02 PM	#21
AckM3 Teh Shuffle Fairiez 51 Rep 1,115 Posts Drives: Teh e92 M3 Join Date: Oct 2008 Location: Teh Bay iTrader: (0)	Sounds about right, I used to avegrage 16.5 in D2, but lately I've been driving carefully in S3, avoiding 7th except on the freeway, and getting I'm 17.2mpg __________________ "It's like being at Thunderhill, only without a helmet" -- Itzkirb riding shotgun with me.
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02-20-2009, 04:11 PM	#22
footie Major General 1122 Rep 8,017 Posts Drives: i5M60 Join Date: Oct 2007 Location: No where fast iTrader: (0) Garage List 2024 BMW i5M60 [0.00] 2022 BMW i4M50 [0.00] 2020 BMW M5 Competi ... [0.00] 2008 E92 M3 [0.00]	I mistakenly tripped the computer while entering the town and got the shock of my life. 7mpg was all I was getting, admittedly the traffic was barely moving but thank god most of my trips are out of town.
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