# Abnormally Poor Mileage then...



## János (Jun 19, 2010)

I notice that my MPGs and average speed are usually pretty close to each other, number-wise.

If I'm averaging less than 20 MPH I'll have low 20s for MPG. 15.3 is a really low average speed so it is not surprising to see such low MPGs.

My car usually stays around 28MPG, with lots of city driving and stop & go freeway driving. The numbers fall dramatically when driving in town (which includes going up some big hills) and especially when waiting at stoplights. Fortunately there are several times during the week when I can drive at the freeway limit. My commutes are usually 15 miles each way, plus one at 30 miles.

The best I've seen is when I filled the tank, reset the computer and set out on an uncrowded freeway. The display showed 42MPG - very impressive... if only I could have kept driving at that speed!

Sadly, after eight months I have yet to take it on a long road trip :tsk: - the "d" is perfect for that.


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## railroader (Apr 12, 2010)

My cumulative average on my "d" is right at 30, but if I zero the computer, fill up and take a nice higher speed road trip, 
it will reward me with mid-30s or higher. I have not had the "software update" on my 2010 car; but the computer is calling
for a scheduled oil change this month (the kind that BMW "pays" for on our maintenance plans.) The tech will probably want 
to install the update; I am thinking about not getting it due to what I've read; ie- lower fuel economy, holding shifts longer, etc.

My car (in the D setting) practically "short shifts" itself up through the range; sometimes so seamlessly I cannot even feel the 
shifts! I rather like that and still get the good MPG. However, unlike some of you guys, I am in a warm winter clime- So. Calif.
I never get frozen "anything." But I'm still getting killed on diesel prices, like all of us...:dunno:


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## Snipe656 (Oct 22, 2009)

My car has had that software update for months now. I just drove it for 100 or so miles today and it shifts perfectly and my mpg is the same average I always have had. I reset my average speed and mpg for every tank and I record the tanks mpg in my log via hand calculations. I have no idea how long it has been mileage wise since I had the update, probably a few thousand miles though.


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## cssnms (Jan 24, 2011)

bimmerdiesel said:


> With that avg speed none of us would get any better than 18mpg. Try 1-2 fuel ups and see how it is.


Au-contraire, I was averaging low/mid 20's during the same commute prior to this tank of gas. I just filled up today from a different station and the station I have historically gone to, so we shall see.


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## DC-IT (Sep 27, 2009)

Snipe656 said:


> What is your average mph though? I'd think his 15.3 mph average means he is not moving much. My tanks with Houston traffic usually netted me around 29mph average speeds with around 27mpg for the tanks. I would notice the more I had to idle or sit in the traffic the more those averages dropped like a rock.


My bad.
You're absolutely correct Snipe656.
I just checked my trip computer and my average speed is 35.42 mph which accounts for my better FE.


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## Snipe656 (Oct 22, 2009)

I have a really hard time believing anyone gets mid to low 20s mpg with a mid teens average mph. But that I'd just me with my almost always sub 30s mpg tanks.


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## DC-IT (Sep 27, 2009)

Snipe656 said:


> I have a really hard time believing anyone gets mid to low 20s mpg with a mid teens average mph. But that I'd just me with my almost always sub 30s mpg tanks.


The BMW US website claims the D's FE is 23 mpg (City) and 36 mpg (Highway).
335d Specs


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## Snipe656 (Oct 22, 2009)

And the EPA average speed for city is 20 mph, a 4.7mph difference can make for a big difference in fuel economy.



> The city test is approximately 11 miles long and simulates a stop and go trip with an average speed of about 20 miles per hour (mph). The trip lasts 31 minutes and has 23 stops. About 18 percent of the time is spent idling (as in waiting for traffic lights). A short freeway driving segment is included in the test. The engine is initially started after being parked overnight.


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## bimmerdiesel (Jul 9, 2010)

also its worth while to check ur tire pressures. I have winter setup with Blizzaks (225/40/18). While installing them I had 35 all around and when I checked yesterday rears were at 32. TPMS will not alarm till u r 4 psi lower. I set it back to 37 lets see if it helps


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## bimmerdiesel (Jul 9, 2010)

Snipe656 said:


> I have a really hard time believing anyone gets mid to low 20s mpg with a mid teens average mph. But that I'd just me with my almost always sub 30s mpg tanks.





DC-IT said:


> The BMW US website claims the D's FE is 23 mpg (City) and 36 mpg (Highway).
> 335d Specs


I dont know how EPA comes up with 23 and 36 But considering weather conditions, kind of diesel and low avg mph I think OPs condition is possible. My mph/mpg for past few fill ups have been 22-24/19-24 and my drive is sub urban with lot of stop signs and partially unplowed roads during snow.

off topic
Other day I was thinking its funny I own $50+k car and I worry so much abt money I spend on my fuel. At sametime I also felt may be I am just worried coz I am seeing unusual mpg figures, Mind defense mechanism are so strong to keep me at peace


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## Snipe656 (Oct 22, 2009)

bimmerdiesel said:


> also its worth while to check ur tire pressures. I have winter setup with Blizzaks (225/40/18). While installing them I had 35 all around and when I checked yesterday rears were at 32. TPMS will not alarm till u r 4 psi lower. I set it back to 37 lets see if it helps


I really wish my tire pressure alarms were that sensitive. Last winter just 2 psi would set them off and that is when I had the original 2009 software which meant when the light on the dash went off it would not tell me which tire was low. So with every major fluctuation in air temps I was outside trying to figure out which or if all the tires needed air.

Although maybe they are that sensitive because this current winter with the new software I have only been alarmed once when the temps dropped massively one day and the alarm was for all four tires but I forget how much I had to add.


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## DC-IT (Sep 27, 2009)

bimmerdiesel said:


> I dont know how EPA comes up with 23 and 36 But considering weather conditions, kind of diesel and low avg mph I think OPs condition is possible. My mph/mpg for past few fill ups have been 22-24/19-24 and my drive is sub urban with lot of stop signs and partially unplowed roads during snow.
> 
> off topic
> Other day I was thinking its funny I own $50+k car and I worry so much abt money I spend on my fuel. At sametime I also felt may be I am just worried coz I am seeing unusual mpg figures, Mind defense mechanism are so strong to keep me at peace


I have a bad habit of not checking my tire pressure!
In fact over tha past 14 months since I got my D I have not cheked it at all! I am GUILTY as charged!
In the mean time my D has had 2 oil changes over the 40,000KM it has put in without any incidents other than the day when all windows + sun roof mysteriously opened after I parked her for a couple of hours.:dunno:

Another thing I am guilty of is not checking the oil level!

Despite all that, she delivers all her goods without any protests and her FE has been exempelary. Even now in the mids of Winter and wearing Winter shoes and drinking winterized Diesel my trip computer is still showing 500 miles/800+ KM driving range!:thumbup:

I promised my D that I will change this year and start checking the tires and oil level starting this Spring.:angel:
I guess I was relying on all the computer chips in the iDrive (TPMS/Service status).

Touch wood, to date the D has been one of the most reliable car I've owned and the most rewarding in terms of performance + FE of all the cars in my life.... well not quite... just this week I bought a 2011 VW Jetta TDI to share the burden of the high mileage I go through each year with the D.

I am looking forward to 2011 driving two Diesel vehicles. No more gassers from now on.:thumbup:

Cheers.


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## Snipe656 (Oct 22, 2009)

bimmerdiesel said:


> Other day I was thinking its funny I own $50+k car and I worry so much abt money I spend on my fuel. At sametime I also felt may be I am just worried coz I am seeing unusual mpg figures, Mind defense mechanism are so strong to keep me at peace


I never worry about the mpg in my vehicles but I have to track all my fillups and as a side effect to that I end up seeing the mpg and just knowing it. Now why I always reset trip meters, mpg meters and average mph meters is something I really have no clue on, just some ritual habit of mine. Now maybe had I paid any where near $50k for any of my cars then I might start worrying if I saw some drastic change in any of those numbers I was paying attention too.


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## DC-IT (Sep 27, 2009)

Snipe656 said:


> I never worry about the mpg in my vehicles ....


+1

My main obsession is with the driving range, since I typically cover between 130~150 miles per day.
My old SUV needs a refuel every second day and it's no fun doing that in deep Winter in -20C!

My D needs a refuel every 3~4 days so that helps a bit.

All I wish for is Diesel that can maybe get a driving range of 1,000 miles and hopefully that will last me a week in between fillups and I'll be a happy camper.
maybe a second fuel tank can be hook up in the trunk?:thumbup:

In that respect the 2012 VW Passat which has a larger tank with the same 2.0L TDI (800 Miles/tank) may just be the answer to my dreams!:thumbup::thumbup:


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## Snipe656 (Oct 22, 2009)

Driving range is also my bigger concern. My truck can go just as many miles and sometimes more than my BMW for my commuting. The truck of course guzzles diesel in comparison but the cost of the fuel does not bother me. I have not been in the newer Passats, would be curious as to how much cargo and interior room they have in comparisons to a 335d. I am though not a fan of FWD cars and seem to remember the Passat being just that.


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## GB (Apr 3, 2002)

DC-IT said:


> In that respect the 2012 VW Passat which has a larger tank with the same 2.0L TDI (800 Miles/tank) may just be the answer to my dreams!:thumbup::thumbup:


I give VW lots of credit for reinstating the diesel option for the new Passat, but sheesh, that car defines bland in most other respects. In terms of range and FE though, it does look like it has potential to be a unique choice for a reasonable priced mid-sized dlesel.

I really wish some automaker (especially BMW or VW/Audi) would offer a diesel AWD compact wagon with a manual transmission and I'd part with my Eurovan, WRX wagon and 335d for one vehicle!

Graham


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## taibanl (Oct 3, 2010)

Update:

Dealer reported no codes. Suggested this MIGHT be due to low cetane fuel (which i admit
Is always a possibility even though i buy only name brand diesel. I will continue to monitor but it woild have been nice if dealer checked the cetane reading which is reported by OBC. 

As i posted in DEF @ 7000 miles, dealer is saying that all is working normally and its definitely due to frozen fluid. This assessment really doesnt make sense (for reasons explained in other thread) but ill continue to watch. 

I WILL be contacting BMW NA about this (more about the car than dealer)


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## cssnms (Jan 24, 2011)

taibanl said:


> Update:
> 
> Dealer reported no codes. Suggested this MIGHT be due to low cetane fuel (which i admit
> Is always a possibility even though i buy only name brand diesel. I will continue to monitor but it woild have been nice if dealer checked the cetane reading which is reported by OBC.
> ...


I have a similar update,,, Since re-filling my tank with a brand name deisel my mileage has improved and back-up to the low/mid 20's mpg's during my city commute I go. :thumbup:


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## bimmerdiesel (Jul 9, 2010)

Me too. Mine went back to usual avg of 28. Temps have gone up a bit, pretty much using same diesel and same commute and no snow aswell


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## anE934fun (May 10, 2008)

taibanl said:


> Update:
> 
> Dealer reported no codes. Suggested this MIGHT be due to low cetane fuel (which i admit
> Is always a possibility even though i buy only name brand diesel. I will continue to monitor but *it woild have been nice if dealer checked the cetane reading which is reported by OBC*.
> ...


What function of the OBC checks the cetane reading?


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