[cdgatti]

Anybody else noticing a nice mileage increase with this 50 to 60F weather in the Midwest after the zero degree crap? I am getting 32.8 on my normal commute when 28 is more the norm. I did just change my 8 year old original battery to a new AGM model. Could that have anything to do with it or is just the mild ambient temperatures or has my new coding hobby screwed up my trip computer?

[W.WCherry]

Warmer air is less dense, so your engine compensates with less fuel, ipso facto better fuel economy.

[cdgatti]

Thanks - I have noticed this in the past too from season to season, but usually just 1-2 mpg difference. I am seeing about 4 mpg increase. I'll have to fill up and see if it actually shows up in the total range I get from a tankful. I normally get about 420 miles per tankful, this will be about a 60 mile range increase.

[cdgatti]

An update... just got back from a long highway trip of about 4 hours. I did the manual calc method of starting with a full tank, driving the distance, than refilling to get actual miles and actual usage. By this method I got 32.5 mpg on this highway trip which I think is good for the N52 and believable to me. My trip computer said I got 39.7 mpg, this number is bogus. What is going on with my trip computer? Could coding somethings in the Kombi have affected it???

[luv135i]

Gas stations are starting to switch to the summer blends.

[MasterWang]

9.8 city and 16 highway here.
I should probably get my car checked out.

[LGCubana]

Originally Posted by MasterWang

9.8 city and 16 highway here.
I should probably get my car checked out.

you're on the wrong thread. the OP is referencing a natrurally aspirated engine.

[Antetokounmpo]

Originally Posted by LGCubana

you're on the wrong thread. the OP is referencing a natrurally aspirated engine.

Under normal driving, the 328i and 335i are supposed to get almost identical mileage. Under WOT it's obviously a different story.. but what he's getting is awful.

[Efthreeoh]

Originally Posted by B.Corso

Warmer air is less dense, so your engine compensates with less fuel, ipso facto better fuel economy.

I guess no point in turbo charging or super charging then...

[Efthreeoh]

You can't make any comparison on fuel mileage with just evaluating what the trip computer says on a random tank of gas to what your memory thinks was your previous MPG average. For the past 25 years or so I've kept detailed hand-recorded and hand-calculated records of MPG; so that's a good 700,000 miles of data over several different cars. I've noticed that the average MPG doesn't change much dependent upon the ambient temperature (i.e. season). I have noticed a maybe slight change (drop) in average MPG during winter months when the EPA started mandating winter fuel formulations, but not much of a change, and certainly not a 5 MPG change. If you keep records of fuel data such as I have you find that there is a much variation in MPG between tanks - a few MPG or so- as compared to over several months as the season changes. There is really no way to make a correlation. In my care for my E90, which I drive a very consistent commute to work every day and rarely use the car for other than work commuting.

For my E90, being that it calculates average MPG per tank I get to compare that to my hand-calculated (Excel) data. The on-board computer is really accurate compared to hand calculation. Below are my data averages over 270,000 miles. Just for grins I looked at the average of the per-tank MPG from the BC (on-board computer) for October 1st 2012 thru March 30, 2013 (26.8 MPG) and the per-tank average for May 1st 2103 thru Sept 30 2013 (27.0 MPG). As you can see, statistically there is hardly any difference.

Yeah, geek-fest, I know. But back in the day the only way to know your car was in need of a tune up was poor fuel mileage. The only way to know you were getting poor fuel mileage was to keep track of it. Back in the day means cars without computer-controlled engines (yes, there were such times when cars had analog carburetors and point ignitions). You had to actually use a pen an piece of paper to write stuff down!

[Aashenfox]

Originally Posted by LGCubana

you're on the wrong thread. the OP is referencing a natrurally aspirated engine.

So, er, turbo owners aren't allowed to participate in fuel consumption discussions? What? I think you're on the wrong thread. NA discussion is thataway -----> http://www.e90post.com/forums/forumdisplay.php?f=35 , this is General Discussion.

I get about 14mpg out of the 335 currently in cold temps for Greece, without much ragging it. I need new plugs and probably air filter. Just waiting for payday.

[cdgatti]

Originally Posted by Efthreeoh

You can't make any comparison on fuel mileage with just evaluating what the trip computer says on a random tank of gas to what your memory thinks was your previous MPG average. For the past 25 years or so I've kept detailed hand-recorded and hand-calculated records of MPG; so that's a good 700,000 miles of data over several different cars. I've noticed that the average MPG doesn't change much dependent upon the ambient temperature (i.e. season). I have noticed a maybe slight change (drop) in average MPG during winter months when the EPA started mandating winter fuel formulations, but not much of a change, and certainly not a 5 MPG change. If you keep records of fuel data such as I have you find that there is a much variation in MPG between tanks - a few MPG or so- as compared to over several months as the season changes. There is really no way to make a correlation. In my care for my E90, which I drive a very consistent commute to work every day and rarely use the car for other than work commuting.

For my E90, being that it calculates average MPG per tank I get to compare that to my hand-calculated (Excel) data. The on-board computer is really accurate compared to hand calculation. Below are my data averages over 270,000 miles. Just for grins I looked at the average of the per-tank MPG from the BC (on-board computer) for October 1st 2012 thru March 30, 2013 (26.8 MPG) and the per-tank average for May 1st 2103 thru Sept 30 2013 (27.0 MPG). As you can see, statistically there is hardly any difference.

Yeah, geek-fest, I know. But back in the day the only way to know your car was in need of a tune up was poor fuel mileage. The only way to know you were getting poor fuel mileage was to keep track of it. Back in the day means cars without computer-controlled engines (yes, there were such times when cars had analog carburetors and point ignitions). You had to actually use a pen an piece of paper to write stuff down!

F30 - I agree 100%, I too am data driven and can appreciate your database of knowledge on your present and past cars. My question is really driven by the obscenely high numbers I am seeing on my trip computer after changing the battery and doing some coding with the BMWhat app. It just doesn't make sense to me. When I hand calculated on at least 1 tank, I got ~33 mpg for the trip which is totally reasonable for the type of driving I did, I just can't understand the high OBC numbers.

[Nitrousbird]

I'm finding my car's MPG calculations are pretty close to my manual calculations.

I'm seeing an increase in fuel mileage for sure. I'm showing 25MPG right now. Other than when I bought it, the car has never been on an extended road trip and is mixed freeway/city/45-55MPH roads on every almost every drive (and I'm typically not driving to save fuel).

I'm actually impressed with the fuel mileage and is better than I anticipated.

[jt335i]

Originally Posted by cdgatti

An update... just got back from a long highway trip of about 4 hours. I did the manual calc method of starting with a full tank, driving the distance, than refilling to get actual miles and actual usage. By this method I got 32.5 mpg on this highway trip which I think is good for the N52 and believable to me. My trip computer said I got 39.7 mpg, this number is bogus. What is going on with my trip computer? Could coding somethings in the Kombi have affected it???

Could be the timing of when you reset the trip computer. Did you reset it when you filled up or at some point when you were on the road?

[Douche]

Temperatures here are measured in Celsius, not Fahrenheit, so wrong thread, I must not chime in.

[asus389]

Yeah the milage has gone up since the dead of winter. Of course I will put the kibosh on that when I switch from my skinny/light snow tires to my wide sticky summer tires. But you know...

[Efthreeoh]

Originally Posted by Douche

Temperatures here are measured in Celsius, not Fahrenheit, so wrong thread, I must not chime in.

Well except when it's minus 40, then you COULD chime in , that seems to blow everyone's mind around here...

[Douche]

Originally Posted by Efthreeoh

Well except when it's minus 40, then you COULD chime in , that seems to blow everyone's mind around here...

Lol yeah!
But my 328 is black, his is white, have you not paid attention? Much more economical when white.
I must not chime in.

[lookalikehuuh]

well then... time to re-evaluate my driving technique. According to my fuelog app i have averaged 21.68 MPG over the past year.

Do you people drive like grandpas and grandmas or something??

[Aashenfox]

I was pondering this, this morning as well. Who buys a fast BMW then drives it no faster than a carnival float...? Oh well, each to his own. Unfortunately, I want to feel the torque from the car, so I remind myself "gotta pay to play".

I must say I admire some people's ability to overcome the temptation to drive faster than necessary.

[Efthreeoh]

Originally Posted by Douche

Lol yeah!
But my 328 is black, his is white, have you not paid attention? Much more economical when white.
I must not chime in.

Oh that's right, I forgot. Our cars with black paint come with a different air-conditioning compressor. The part number is

5121BIGASSHITCOMPRESSOR.

[cdgatti]

op checking out... total waste of time.