Posts about MPGs (fixed?)

[whitebimmer09]

I have 68k on it, I have all new injectors, all new plugs.

I mean other than the way I drive, is there something that can cause this?

The problem is I can get less, like 140 to a tank. Maybe I drive like an asshole and I don't realize it. Very possible.

[febul]

Originally Posted by Vigilante375

And on another note.....anyone complaining about a sports car MPG needs to find another car to drive.

Also, EPA numbers don't mean jack. They are well below what any vehicle can really achieve.

I think that it's something that deserves attention when the MPG is significantly lower than what it should be though...

[MightyMouseTech]

It is just a standardised test to compare all cars, nothing more. Did you know the average speed of the "highway" rating is only 70 km/hr?

I can beat the highway rating when cruising, but around town with stop and go driving, I am hard pressed to get the "city" rating.

Also, for best fuel economy, you do NOT want to accelerate very gently. To get good FE, you need as much constant speed driving as possible. You want to accelerate to your cruising speed fairly quickly and then completely stop accelerating as soon as possible and cruise at a steady speed. Get the car into closed loop operation. If you are constantly accelerating, even slightly, you will be in open loop operation and the FE will be terrible.

This is even more important when driving a car with a turbo. While under boost, the engine needs to run richer to keep everything cool compared to a naturally aspirated engine. You need no boost, steady state driving to get into lean burn conditions. What makes this even worse is driving while the engine is warming up. The engine runs richer because the fuel is not getting fully atomised below operating temp, so the computer will run it a bit rich to compensate. So, driving with the engine not fully up to operating temp, constantly accelerating lightly will destroy the FE. You can't beat the laws of physics.

Maybe the OP should get an i3 to drive to work and back, they don't care about short trips, nothing to warm up.

[ejm3]

Something seems amiss to me.

I get between 24-26 MPG and close to 300 miles on a tank in mixed driving.
A little less if its mostly city driving, more if its all highway.

I'm bone stock, 6-speed MT, top down 99% of the time. I get on it occasionally but mostly I don't drive it too hard.

[JeffyD]

People often fudge their numbers on the internet. No idea why, but if you take them all seriously, you'd be under the impression that everyone bought their car for 15k under TrueCar and all men have difficulty finding comfortable pants to fit the 10"s they're packing.

Quick and dirty - a 350 mile trip in my N55 equipped 'is pulled back 31.something after heading north on the CA I5 right after the Grapevine was discounted from the scorecard. Tires were set up for speeds focused at between 75-85 MPH.

On the way back, I got 28mpg taking the same route south. Difference was brand new super sports installed and being burnt in. And also more than a few miles spent screwing with the typical Civic/Accord dude trying to outpace everyone dangerously while pushing their VTec at 87mph. So that translates into dropping into fifth and blasting to speeds my lawyer tells me are still "alleged."

City driving with the car is avoided as much as possible, and I've never bothered checking since I lack the maturity to go one tank of gas without a lot of "spirited" canyon bombs at 2am. So I won't BS you here... Screw it. I get 45mpg while on the 405 parkinglot.

[Chunner]

haha... i had to stop checking because I was getting such horrible mpgs. 15.2 mpg is what I have today.

[Ed P]

Originally Posted by JeffyD

People often fudge their numbers on the internet. No idea why, but if you take them all seriously, you'd be under the impression that everyone bought their car for 15k under TrueCar and all men have difficulty finding comfortable pants to fit the 10"s they're packing.

Quick and dirty - a 350 mile trip in my N55 equipped 'is pulled back 31.something after heading north on the CA I5 right after the Grapevine was discounted from the scorecard. Tires were set up for speeds focused at between 75-85 MPH.

On the way back, I got 28mpg taking the same route south. Difference was brand new super sports installed and being burnt in. And also more than a few miles spent screwing with the typical Civic/Accord dude trying to outpace everyone dangerously while pushing their VTec at 87mph. So that translates into dropping into fifth and blasting to speeds my lawyer tells me are still "alleged."

City driving with the car is avoided as much as possible, and I've never bothered checking since I lack the maturity to go one tank of gas without a lot of "spirited" canyon bombs at 2am. So I won't BS you here... Screw it. I get 45mpg while on the 405 parkinglot.

LOL... best response. Evar.

[Vigilante375]

Originally Posted by febul

I think that it's something that deserves attention when the MPG is significantly lower than what it should be though...

I guess but when its true city driving, stop and go traffic then you're going to be getting a lot lower MPGs than what the car is rated for. Especially when its hot out.

[JeffyD]

Stop. Go. Stop. Go. Stop. G-oh shiz, swerve. Gosh darn 16 yearold Audi driving girls with important texts to take care of. Stop. Go. AC needs to be cranked lower. Why is it so hot today? Seriously? "Road work" my behind - plenty of cones for a job that takes zero men to do. Unless they're invisible. Or construction working ghosts. Do they even allow spirits walking the Earth into union? Well, I guess they have rights, too... Oh no, I've turned into my father by being a ghost racist. Ugh, theraaaapy.

That, a common scenario in the city, translates into figures WELL below rated MPG. But I understand that it's YOUR car, and you're going to worry about it. From a third party perspective, though, it doesn't seem abnormal.

And it's not just supportive conformational denial, dude. Like when people compliment other people's kids. That drawing sucks, but no one will say it.

[JimD]

I drive a 128i. I keep a notebook in each of my 2 cars and write down mileage, gallons, and cost each time I fill up. I believe this is the only accurate way to get your mileage and single tanks don't count for much (because of the difficulty in filling to the same point each time). I keep track of cumulative and average of last 3. Over time, the difference in fill up level is not an influence but in the short term it is. The mpg display available in the car depends on a relatively inaccurate flow measurement. It isn't terrible and may be better than a single tank calculation but is not as good as keeping up with multiple tanks.

My spreadsheet was last updated in late 2012 when I was around 23,000 miles. My average at that point was 27.2 mpg. I also track miles to the warning light and that is around 300 miles. I've gone over 350 miles on a tank a dozen times or so. Normally I fill up before getting that low. I have the data to get to today in my notebook, I just haven't entered it into the spreadsheet.

13 seems really low to me. Things that kill mileage include stop and go driving, quick starts, quick stops, and high speed driving. I think "Stig" said he was below 20 in his 128 due to aggressive driving. My wife says I drive like an old lady most of the time (on the other hand she says she is scared sometimes). My commute has some stop and start but is a mixture with only about 1/3 having frequent traffic lights. Another 1/3 is on the highway. I average around the highway rating for my vehicles in my mixture of highway and city driving. So my wife probably has a point (hopefully she won't read this).

[amyracecar]

the onboard computer and its "estimations" are more off in my 1 [2011] than my 97 e36 328 or 01 e46 m3... all MT

that being said i get around 24mpg in the 1er [same in the e36 and about 20 in the e46 M3] - and 280 mi per tank - i used to do the math every time i got gas but it was so consistent i quit and now i just makes sure it is close to on target or i start to worry about something being wrong - so far so good

seems from reading this thread that others get similar #s so I feel better - most of my driving is rural/hwy with little stop and go and i can get the mpg down below 20 w/ little effort and have found "how" i use 6th gear makes a big difference in the final mpg calculation as it took me a little bit to get used to having 6th

in the end my shifting patterns and affinity for the gas pedal have a huge part in determining my mpg - but the computation at the gas pump helps me know if something else is going on

[TwinTurboed]

I am surprised by all the folks who are getting 13-17 MPG. I drive about 70% city, 30% hwy and I average between 19-22 depending on how I drive that week. I get between 270-300 miles per tank and I drive the car like its meant to be driven. N54 6MT.

[whitebimmer09]

Originally Posted by TwinTurboed

I am surprised by all the folks who are getting 13-17 MPG. I drive about 70% city, 30% hwy and I average between 19-22 depending on how I drive that week. I get between 270-300 miles per tank and I drive the car like its meant to be driven. N54 6MT.

How is that surprising? They are rated at 18/25. I find is surprising that people actually say they get more than 18 in real city driving. on the freeway I can understand, but in light to light driving, forget about it.

[MightyMouseTech]

I usually get better than 13 L/100km (18 MPG) in pure city driving, but not much. I can do much better than (9.4 L/100km) 25 MPG on the highway. One thing I like about our cars is that there is not a large difference in FE anywhere from 110 km/hr - 130 km/hr. So I usually cruise at 130 km/hr and have seen tanks as good as low 8's L/100km (29 MPG)

For in city driving, see my previous post about steady state driving.

[TwinTurboed]

Originally Posted by whitebimmer09

How is that surprising? They are rated at 18/25. I find is surprising that people actually say they get more than 18 in real city driving. on the freeway I can understand, but in light to light driving, forget about it.

It's surprising because I have an N54 w/ 6MT and I drive with a heavy foot and still get 19-20 mpg in the city.

[Ed P]

My previous car (which was up until two weeks ago ) was a 2006 Mazda MX-5, where I got about 31.5 mpg in a "normal" driving week, and about 34-35 pure highway. I knew I'd take a slight hit on mileage going to the 2013 135i of course.

First refill where it was all "normal" driving since I got the 135i was today. About 70%/30% hwy/city driving: 26.2-26.5 mpg. (26.5 if you calculate when the pump shut off; 26.2 if you calculate after I put in a little more to "top it off").

Highway driving (approx 70% of miles on this tank) is 65-80 mph, average of about 73. City driving (approx 30% of miles on this tank) is 0-50 mph, average of about 40.

I'm pretty happy with this. That means I'll get about 30+ mpg on the highway on a trip.

[ShocknAwe]

Averaging 40mph driving through town is not city driving. That is cruising and will pretty much get you highway mileage. If I misunderstood you then carry on.

[Ed P]

Originally Posted by ShocknAwe

Averaging 40mph driving through town is not city driving. That is cruising and will pretty much get you highway mileage. If I misunderstood you then carry on.

My average of 40 (guess) failed to emphasize the stop-and-go part, which there's plenty of in my "city driving".

[Deutsche-Broke]

Originally Posted by JeffyD

And it's not just supportive conformational denial, dude. Like when people compliment other people's kids. That drawing sucks, but no one will say it.

Christ.. You are on fire this evening.. Beautiful..

"Yes folks, He'll be here all week. Don't forget to try the Veal, and please remember to tip your server.."

[whitebimmer09]

So I have been talking about getting poor mpgs and this time I got to 248 miles on my last tank. That's around 18 mpgs. Now keep in mind I just got an exhaust and I have been playing with it. I had my injectors replaced last week after some difficulties starting, nothing with my driving habits changed. I'm going to blame that. Very impressed now.

[Fume]

Originally Posted by Ed P

My average of 40 (guess) failed to emphasize the stop-and-go part, which there's plenty of in my "city driving".

The typical "city" driving varies so much from city to city to be able to meaningfully compare. For example, when I drive in downtown Seattle, I'm lucky to be going over 30mph. It's literally 15-20mph max speed, probably averaging under 10mph if you count all the time waiting at stop lights and then waiting for slow/jay-walking pedestrians at the cross walks. And of course each city block downtown is probably half the distance of a block in the suburbs.

Anyway, driving condition matters a lot. When I drove to Portland, easily averaged 29mpg without trying to be economical. Driving during my rush hour commute, I average 19-20mpg since it has some highway driving although it's bumper to bumper stop and go during rush hours maybe half the time. And luckily I don't have to actually drive through downtown Seattle too often.

[msf]

I use Gas Cubby on my phone to calculate mpg. The computer on my cars have always been off to the high side. The 135is computer calculates about one mpg high. To get true mpg you have to divide total miles driven since the last fill by the number of gallons. It is best to do over time for a true average. The app makes it fast and easy to do and keeps the history for you. I drive 50/50 hwy/city. I drive in sport mode with DSC off always. I drive fast with fast acceleration from a stop. I have the DCT. I average 24.8 mpg. My mpg improved when I started taking the DSC off.