E92 Fuel Economy

[E92Vancouver]

Does my car burn a lot of fuel or does my fuel consumption computer need calibrating? I have the 328 coupe.

When driving easy, I only get 12 to 13 mpg in the city. When starting off as easy as possible from a stop, my instantaneous fuel consumption display shows I am only getting 6 mpg????? WTF????

I'd like to hear from 328 and 335 owners.

[neapolitan]

Yeah, discussed here in the forums quite a bit, even recently -- you might want to do a search and find some of the older posts.

IIRC xi gets a little worse than i models. Real world averages (for 328 sedan) was 16-18 mpg city and mid to high 20's for highway.

I have a 328xi sedan, get 16 mpg pretty consistently in the city (can't figure out why -- doesn't seem to matter one bit how much A/C I use or driving style). Oh well.

I don't think easier driving past a certain point will help you at all. After all, cars are most fuel efficient circa 40 mph, so if you are accelerating quickly to maintain a high speed that is ok. The waste from rapid acceleration is less than energy losses from changes in speed. By this I mean rapidly accelerating to get on a highway ramp is relatively small amount of energy wasted compared to getting up to 45 mph then braking down to 0 at the stoplight 20 meters ahead, then repeating the process, which I see people do all the time. Meanwhile I just cruise by in third at a steady 25...

Do you have auto or manual?

[Danny 335i]

I have only 1K miles on my 335i coupe (6MT) and am getting 20mpg local.I started off at around 18,and as the miles increase so does my mpg.I havnt checked the highway mpg yet. I,m sure when i get around 5-6k miles i,ll be getting at least 22-23 local.My last 3 cars were all the same.The more the motor breaks in the higher the mpg got. Of course thats driving like a semi normal person (LOL). I,m sure if i wanted to i could get 12 mpg also.

[Slvr335I]

I have a '07 335I (1100mls) and on the highway I get 30-32mpg. In the city I have been steady at 22-24mpg. Mine is a automatic. I reset my gauge after each fill up to keep track of what I am getting.

[Arustik1]

I have a E92 335i MT and i average 18.5 mpg in the city and over 20 on the hwy. I drive fast...pretty fast, but I do know if i drive a certain way ill get less than 15 mpg. I have no idea how youre getting 12 mpg with a 328. You might want to reset your computer...bring it into the dealer.

[mryakan]

Does my car burn a lot of fuel or does my fuel consumption computer need calibrating? I have the 328 coupe.

When driving easy, I only get 12 to 13 mpg in the city. When starting off as easy as possible from a stop, my instantaneous fuel consumption display shows I am only getting 6 mpg????? WTF????

I'd like to hear from 328 and 335 owners.
How often do you reset your computer? If you just reset it after 10/15 minutes or so of stop and go traffic, you will get bad gas mileage, even my 323 gets really bad economy right after I reset the computer in the city. You need to leave it on for a much longer time.
Say you measure it in a traffic jam, I wouldn't be surprised you get lousy numbers because of the small distance you move vs the fuel consumed. Hope I made sense and conveyed my point.

[UFOGUY]

15-18 mpg city, due mainly to numerous short trips.

highway mileage is excellent at 30-32 mpg @ 75mph.

[psucelticXI]

How often do you reset your computer? If you just reset it after 10/15 minutes or so of stop and go traffic, you will get bad gas mileage, even my 323 gets really bad economy right after I reset the computer in the city. You need to leave it on for a much longer time.
Say you measure it in a traffic jam, I wouldn't be surprised you get lousy numbers because of the small distance you move vs the fuel consumed. Hope I made sense and conveyed my point.

I got what you were saying...

[E92Vancouver]

Yeah, discussed here in the forums quite a bit, even recently -- you might want to do a search and find some of the older posts.

IIRC xi gets a little worse than i models. Real world averages (for 328 sedan) was 16-18 mpg city and mid to high 20's for highway.

I have a 328xi sedan, get 16 mpg pretty consistently in the city (can't figure out why -- doesn't seem to matter one bit how much A/C I use or driving style). Oh well.

I don't think easier driving past a certain point will help you at all. After all, cars are most fuel efficient circa 40 mph, so if you are accelerating quickly to maintain a high speed that is ok. The waste from rapid acceleration is less than energy losses from changes in speed. By this I mean rapidly accelerating to get on a highway ramp is relatively small amount of energy wasted compared to getting up to 45 mph then braking down to 0 at the stoplight 20 meters ahead, then repeating the process, which I see people do all the time. Meanwhile I just cruise by in third at a steady 25...

Do you have auto or manual?

I have the manual. My 323 E46 sipped fuel compared to this little pig.

[E92Vancouver]

How often do you reset your computer? If you just reset it after 10/15 minutes or so of stop and go traffic, you will get bad gas mileage, even my 323 gets really bad economy right after I reset the computer in the city. You need to leave it on for a much longer time.
Say you measure it in a traffic jam, I wouldn't be surprised you get lousy numbers because of the small distance you move vs the fuel consumed. Hope I made sense and conveyed my point.

Yes you did make sense. I am picking u[ what yo are putting down. My commute to work is 1 mile and takes 15 minutes of driving. Half of this time is in parkades. But driving from a start, being very easy on the throttle, my instantaneous fuel consumption computer reads 6 mpg until I hit about 30 mph. I have the 6 speed.

[Frank ZZR]

I have a 328 that usually reads around 21-22 MPG in the city. However after I do the calculations I find that it is around 25-27 MPG in the city. I believe the computer is not set to Canadian Imperial gallons so I just usually add 4 MPG to the computer read out and that is very close.

[Naxos]

328xi got 29mpg on my last highway trip.

[ProRail]

Yes you did make sense. I am picking u[ what yo are putting down. My commute to work is 1 mile and takes 15 minutes of driving. Half of this time is in parkades. But driving from a start, being very easy on the throttle, my instantaneous fuel consumption computer reads 6 mpg until I hit about 30 mph. I have the 6 speed.

Until your temp gauge hits the midpoint you will get lousy mileage.

[mryakan]

I have a 328 that usually reads around 21-22 MPG in the city. However after I do the calculations I find that it is around 25-27 MPG in the city. I believe the computer is not set to Canadian Imperial gallons so I just usually add 4 MPG to the computer read out and that is very close.
hmm interesting, never thought of that. Are you sure it is Imperial gallons or just a guess? In this case add 20% to the average 21.7 I am getting and I am at 26mpg American which is my 318ti used to do. Pretty good.

[Frank ZZR]

hmm interesting, never thought of that. Are you sure it is Imperial gallons or just a guess? In this case add 20% to the average 21.7 I am getting and I am at 26mpg American which is my 318ti used to do. Pretty good.

Just a guess but I'm pretty sure. For example, I was showing 21.7 mpg earlier this week on my onboard computer. When I filled up and did the math, (converted litres into imp gallons, L divided by 4.54 and kms into miles, kms divided by 1.6) I ended up with about 26.3 mpg.

[joeygott]

I drive my 335 aggresively and get 18-20 city and 26mpg at 82mph on hwy, 28mpg at 75mph, 30mpg @65mph.
These are DEAD ACCURATE, per measurement with calculator, not just the car trip computer.
I will say this though, the trip computer is MUCH MORE accurate in this car than any other I've owned.