What E34 gets best gas mileage?

[James]

just curious
-James
89 525i 285k miles

[Paul in NZ]

and the worst would prolly be the 535ia

[Anton CH.]

I bet the 518 does well.

[dca]

I have 520i manual. It consumes 5.9 liter per 100 km. on 93 octane gasoline.(high way - 90km/h)

in city it is 11 liter per 100 km.

[kentish]

What about the 540ia. Is the worst than the 535ia

[jplacson]

Man, I wish I had the M50 version!!! My 520i (M20) burns a bit more than that on 95 octane. I hit about 9-10 liters/100km on the highway, and about 14liters/100km in the city! This is according to the economy gauge. Does this sound right? Is there anything else I can do to improve fuel efficiency on my 520i?

[dca]

I have no experience on M20, but it is 8 valves. this means it is flexible on lower rpms. but it is less powerfull. 9-10 liter/100 km is too much, but it depends on the current condition of your car,and your reactions to the road conditions.(on of my friend told me that he has similar milage with you, and he is surprised why my car is so, his engine was m50)

I have 205/65/15 pirelli winter tires which has more drifting than all weather tires. I am sure that I can have better milage with 195/65/15 orginal tires.there should be enough air inside your tires as well.

Also air filter is too much important, engine should get clear air without any restrictions. it should use cold air. orginal box is best.

spark plugs has a great effect on performance. use orginals, because it make no difference, use bosch.

use a good motor oil, forexample magnatec is very good. check your brakes, they could be always "on". use your a/c only if you really need it.

never step on gas, use it gently, be patient, do not hurry accelerate it.

do not trust in economy gauge and fuel gauge, they always show wrong, my fuel gauge always show less.

when it is not warm, wait for it to get warmed for 2 or 3 minutes in winter. go on your way but before it passes the blue mark, oxgen sensors are offline so, it is open loop, it consumes really much, do not step on the gas to much. it consumes really much,approx 40 liters per 100 km. (one option, your oxygen sensors could be faulty - this cause same result)

clean your injectors, if it is not cleaned.( It might not be necessary)

lastly there should be air flow meter on your engine, when I disconect it(then I forgot it)it consumed %20 more.

I hope these help.

Cosku from Turkey

[Jeff N.]

just curious
-James
89 525i 285k miles

[James]

I have no experience on M20, but it is 8 valves. this means it is flexible on lower rpms. but it is less powerfull. 9-10 liter/100 km is too much, but it depends on the current condition of your car,and your reactions to the road conditions.(on of my friend told me that he has similar milage with you, and he is surprised why my car is so, his engine was m50)

I have 205/65/15 pirelli winter tires which has more drifting than all weather tires. I am sure that I can have better milage with 195/65/15 orginal tires.there should be enough air inside your tires as well.

Also air filter is too much important, engine should get clear air without any restrictions. it should use cold air. orginal box is best.

spark plugs has a great effect on performance. use orginals, because it make no difference, use bosch.

use a good motor oil, forexample magnatec is very good. check your brakes, they could be always "on". use your a/c only if you really need it.

never step on gas, use it gently, be patient, do not hurry accelerate it.

do not trust in economy gauge and fuel gauge, they always show wrong, my fuel gauge always show less.

when it is not warm, wait for it to get warmed for 2 or 3 minutes in winter. go on your way but before it passes the blue mark, oxgen sensors are offline so, it is open loop, it consumes really much, do not step on the gas to much. it consumes really much,approx 40 liters per 100 km. (one option, your oxygen sensors could be faulty - this cause same result)

clean your injectors, if it is not cleaned.( It might not be necessary)

lastly there should be air flow meter on your engine, when I disconect it(then I forgot it)it consumed %20 more.

I hope these help.

Cosku from Turkey

[tim]

My 540 gets pretty good mileage once you get it up to 80-90mph. I did Austin to Dallas in an 2 hours flat once (safely, btw, for those like myself who are conscientious, but enjoy a spirited jaunt every now and then...) and got 24mpg. Overall it sux though ;)

In a few years gas is going o be $20 bucks a gallon. Live it up while you can.

[Scott E]

Parked and with the engine off I assume... lol

[Paul in NZ]

from surveys we have had on the board the 540 quite often is better than the 535..... :(


What about the 540ia. Is the worst than the 535ia

[Tiger]

17 city and about 25 highway

[dca]

It is more responsive on low rpm, m50 is 24 valve engine, m20 is 12 valve(on previous post I was wrong, I tried to say 12valves ). so it respond gas better than m50 when rpm is low(torque is available on lower rpms), so you dont need to downshift. but on high engine speeds it is weak, that is why m50 is accelerating better when car is moving fast.

[epp]

my e34 does 5.2km/lit (OBC and manual readout similar) roughly 19lit/100km on 93 octane. all stock and loves all the petrol she can take. :)

rgds,
ed
90/535ia

[jplacson]

Hmm...maybe I just have a heavy foot! hehehehe.

I'm running 225/45 R18 Dunlops (they came with the car, I'm upgrading to Michelins when they need changing)

I just got my car out from Inspection 2 at the dealers. Air & fuel filters were changed, oil (Castrol) was changed as well... spark plugs were still ok, so they didn't change those. Valves were adjusted as well (or so they say anyway) A/C is always on (I live in a VERY tropical country)

I will try to clean my injectors, check the O2 sensor, and my AF meter.

Thanks.

I'm running 95 octane fuel.

[dca]

ofcourse if it is not running, if it is running milage is worst, infinity consumption/per mile.

[TheGeak]

the ///M5 did about 16city/25highway. if i was really light footed i could get about 28-29 highway. But who drives an M5 with a light foot?

[jplacson]

I have 205/65/15 pirelli winter tires which has more drifting than all weather tires. I am sure that I can have better milage with 195/65/15 orginal tires.there should be enough air inside your tires as well.


I'm running 225/45/18s (36psi all around)... would this increase or decrease my milage? What effects would high performance tires have on milage and why? (Sorry for all the questions... new Bimmer owner... never was a gear head, so all these things are quite new to me)

[TheGeak]

proper tire pressure ensures that you have the optimal part of the tire in contact with the road. underinflated tires provide a lot more surface area to come in contact with the road, thus increasing friction, and reducing MPG. If you just make sure you have your tires filled to what it says on the sidewall you should be getting optimal mileage. Make sure to check monthly though, and as temperatures change drastically!

can't help you all that much with the 'types of tires' vs 'mpg' question though. I have a few ideas, but i'm not sure if they're correct or not.

[jplacson]

Just wondering though, since this is the first car I've ever owned that needed low profile tires...

I asked a few people, and they said 225/45/18 should run about 36psi.

But when I brought my car in for an Insp. II at BMW, they filled the front to about 41psi, and the rear 36psi... does this sound right? Should I stick with this setup running my tires? Or go with 36psi all around?

[TheGeak]

depends on the time if year for me. if its winter i'll go with lower psi all around for better traction in snow. However if i'm going to do some spirited driving, i'll fill up to about 41-42psi front and 38-40psi rear. Thats just my preferance though. I was running 245/65/17 (i think thats what i had on)

[jplacson]

Ok... just wanted to verify, cuz I've never had tire pressure that high before... nor did I ever have higher psi in one set over the other. Just checking. Thanks! :)

[TheGeak]

low profile tires want high pressure since they have stiffer sidewalls and less "bounce room" than your average thick walled tire. I'm no expert on this, so definatly don't take my word for the gospel, but i've heard that higher psi in the front usually equates to better handling.

What 18" rim are you running?

[jplacson]

They came with the car. They are replica BMW style 95 wheels. Wheels are pretty expensive here in the Phil, so replica or not, I don't really plan to change them anytime soon. I'm using Dunlops though (also came with the car), and I've heard they aren't that great in handling or road noise... so once they've worn out (maybe in a year or two) I intend to switch to either Continentals or Michelins (I'm really eyeing their new ZP line found on the new 5-series)

Hmmm... I might go back to what BMW placed in my tires to begin with... 41 front, 36 rear. I mean, they should know better than me right? I just was a bit freaked since most NORMAL tires don't go over 36psi. Oh well... learn something new everyday! :) And with this being MY first Bimmer, I'm learning a lot of things that are done differently over Japanese cars.

[TheGeak]

i know some people that have run 48psi in their's all around (don't know WHY, but they did) and didn't have any problems.

I'd check tirewalls first and see what the TIRE recomends. Normally the tire company knows even better than a car manufacturer!

[jplacson]

well, it only says the max psi which is about 50++ psi.

[Warren N.CA]

:p


just curious
-James
89 525i 285k miles

[TheGeak]

M5? 54ia?


huh?!

[Warren N.CA]

in Montgomery, AL, in 1968. I asked the salesman what the gas mileage was and he replied:

"If you have to ask, you cain't affohd it."


just curious
-James
89 525i 285k miles

[TheGeak]

i was more curious as to what the 54ia was?

[jplacson]

Perfect example of environmental irresponsibility. Just cuz you can afford a truck of gas a day, doesn't mean you should burn it all. That's just plain stupid.

BMW engineers are concerned with fuel economy, that's why they have those consumption gauges. The whole point is to get the most horsepower per liter of displacement... not the LEAST.

In the Philippines, we're flooded with Ford Expeditions (that probably didn't sell well in the US) ... 5 liter V8 engines... in a country that has traffic so bad, it take 30-45 mins just to travel about 10 miles on a regular day.

I'd be willing to a buy a Hydrogen upgrade for my E34 if even BMW comes up with one.... or for the short term, one of their new diesel engines found on the new 5-series!!! 0-60mph (0-100kph) in 8 sec, top speed of 150mph (250kph) electronically limited. All from a dead silent diesel engine, that hits peak torque at 2000rpm! All of that without sacrificing diesel economy!!!! ... I'd love to have those new 530d engines in my E34!!!!!!

[shoptb]

I get 22 city / 29 highway with my 530iA (Alusil).

[Bigezvol]

23-24 city... M50

[winfred]

at 70 mph on a 1100 mile trip, over several trips best 27.5 worst 21.7 in the 535, i usually get 18-19 intown. just last week i checked my 325 and was suprised, i usually get around 23.5 on my normal work week, about 16 miles hwy 4 street, with plenty of thrashing, 25.6 mpg, i abused it as normal, i need to take the 3 on a trip to see what it can do now, the last time i took it to VA i got almost 30 but i've done a lot of work on it since then and most everything i've done has gotten a small increase in mpg

[Captain Case]

Man, I wish I had the M50 version!!! My 520i (M20) burns a bit more than that on 95 octane. I hit about 9-10 liters/100km on the highway, and about 14liters/100km in the city! This is according to the economy gauge. Does this sound right? Is there anything else I can do to improve fuel efficiency on my 520i?

I think the 2 liter M20 is not the best choice. My M20 is a 2.5 liter block which still does about 9l/100 km at 160 km/h on the highway, which is better than most small cars at this speed. City mileage is about 12..13l/km.

[zakjob]

3 weeks ago me and my dad drove from houston, tx to Kennewick, wa. averaged something like 19mpg overall. Cost well over 200 bucks in gas, at 1.80 a gallon it really racked up quick.

[David Chen]

My 540i/6's best -- 27 mpg -- Great Falls, MT to Bismarck, ND on one tankful averaging over 75mph, that's over 550 miles.

-- worst -- 9 mpg on track day.

[molesz]

I got the M50B20 engine ('91 520i e34, 5spd manual, 17" Borbet wheels with 235/45 M+S tyres, no tuning) and the fuel consumption is just about the book say it should bee: city driving 12 l/100km normal accelerating shifting gears arround 2000-2500 RPM and accelerator pedal pushed max 2/3 of its way, highway at 60km/h=5,9l ; 80km/h=6,1l ; 100km/h=7l ; 120km/h=8l using 95 octane unleaded and a wife +kid +package.

I saw you got some good tips but I would like to ad that the proper tyre preassure is critical (even rising the pressure for 0,2bar over the declared can lower the fuel consumption for about 5-7% - ok you got a bit harder ride and a bit more wheel noise but worth trying), shifting gears as soon as possible to 4th or 5th, on hot days driving on the highway with the A/C on is more economical than with the sunroof and windows open.

[molesz]

I think that its not all right ... i dont know the exact preassure for those tyres but the rear tyres must be allways at higher preassure then the front!

[MsInspired]

Best was 22-23 mpg highway, but now I'm motivated to tune-up and see what this ol car can do.

[JR'Z 525]

I average 22-23 going 18 miles of rural hwy with some stop and go during a normal week. Out on the road the best I've ever gotten was 27. It kind of interesting watching the OBC's mpg go up and down during various driving conditions.
JR

[winfred]

i just filled the 535 19.6 mpg on my normal loop, with the usual amount of flogging, the obc is about 1 mpg low from actual, but has been 3 or more low

[Paul in NZ]

about 27 mpg(imperial gallons) at about 110 km hr on the drive back to Wellington from Auckland.NZ is a hilly little country and i also wonder if the cat less cars without the o2 sensor use more gas than the 535 with .It is very hard to get the guzzle o meter below 10 l 100 ks even on a flat smooth highway(28 mp per imp g)Thats about 23 miles per US gallon

[dca]

well, important thing is the drag coefficient-firction of your tires. actualy this is related to design of your tire and the material properties that were used.

for example snow tires on same size consumes 20% more. it is not related to the size. always weight same on each tire,right?

[ryan roopnarine]

the eat chip has drastically improved my gas mileage....at a 400 mile drive at an average (obc) of 74 mph, i got almost 28mpg. at 57 mph on a level road, i can get a sustained mileage of 32.5 mpg....these figures are with my 215 lb fatass and a 160 lb person in car, (ac on 50% of time) and frt 34/rr 36 tire pressure.

[BFEINZIMER]

my 535iA kills 12-13 city i fill up once a week its now $65 bucks to fill up

[Dave M]

Wow, this is a crusty old thread

[winfred]

yea really, i still had my 535
http://members.cox.net/wdixon27/rivershot.jpg
replaced by
http://members.cox.net/kitlou/beast1.JPG
:D http://members.cox.net/wdixon27/smokeout.gif


Wow, this is a crusty old thread

[Ferret]

Lol there's a lot of 20's in this thread, scary.

My busted 525i used to get 17 average, but the TDS gets 38-40 on a long run.