petrol consumption

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RichP
Joined: Wed 20 Feb, 2013 00:47
Posts: 190

  Z3 roadster 1.9

petrol consumption

Post by RichP »

Just out of interest, roughly what kind of miles do you get out of your z3's?

Dont know the mpg (its too late to do maths right now) but i get around 40-50 miles out of £10 at todays petrol prices. This is on a 1.9 16v.

I've always thought this was pretty poor milage, but kind of accepted that it wont match my daily diesel.

might be useful to see if mine is running as well as it might. also good to know as i'd like to buy a 2.8+ when i stumble across a couple of grand.

My friend who had a 3.0 z4 said he barely noticed the increase in consumption over the 2.0.
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billz
Joined: Mon 22 Mar, 2010 20:09
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  Z4 roadster 3.0si
Location: nottingham

Re: petrol consumption

Post by billz »

We have the 3.0 Z3 and get around 28mpg on short runs and around 32mpg on long runs. The 3.0 is supposed to be the most economical on mpg over most of the other Z3s. A lot depends on how you drive, if we do a spirited drive then it drops to around 24/26mpg
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Captain
Joined: Thu 28 Jun, 2012 06:43
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  Z3 roadster 2.8
Location: Durban

Re: petrol consumption

Post by Captain »

All depends on the right foot :D I have a 2.8 which gets driven hard so never really worried about fuel consumption, but would say it's heavy judging by the mileage I get out of a full tank.
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Brian4
Joined: Mon 19 Dec, 2011 19:02
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  Z3 roadster 3.0i
Location: Hinckley

Re: petrol consumption

Post by Brian4 »

I have just noticed that our 3.0 has decreased recently so with a bit of rooting around I found the intake hose to the throttle body is split allowing more ir in so the car is overfuelling so might be worth checking the inlet system. I would guess the recent cold weather has caused havoc with old rubber parts.

Off to source a new one now.
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Southernboy
Joined: Thu 07 Oct, 2010 12:39
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  Z3 roadster 3.0i
Location: Johannesburg

Re: petrol consumption

Post by Southernboy »

aprox 500kms / tank...steady 130kph...city driving is a nightmare and the stop / start stuff makes a mockery of the concept of k/litre, so I don't bother woth that.
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tangomachine
Joined: Thu 11 Oct, 2012 22:05
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Re: petrol consumption

Post by tangomachine »

1.9 16v locally I get about 170-200 miles out of £40. best I've ever got was from a full tank I was just over half full after 250 miles on motorways and dual carridge ways. At the end of the day we don't buy these cars for their mpg. I do get some weird looks from non petrol heads when I say this!
TR4man
Joined: Wed 24 Oct, 2012 13:34
Posts: 431

  Z4 coupe 3.0si
Location: Woore, Near Nantwich, Cheshire

Re: petrol consumption

Post by TR4man »

tangomachine wrote:At the end of the day we don't buy these cars for their mpg. I do get some weird looks from non petrol heads when I say this!
I know just what you mean.

I use mine as my everyday car, often driving upwards of 650 miles a week. A number of colleagues have asked me what the MPG is and the look on their faces when I reply "I've no idea because I'm not bothered" :lol:

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PCSAM
Joined: Sat 13 Aug, 2011 01:19
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Location: Taynuilt

Re: petrol consumption

Post by PCSAM »

I get smiles per gallon :D
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seasurfer
Joined: Sat 22 Aug, 2009 13:02
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  Z3 roadster 2.2i
Location: South Lakes, Cumbria

Re: petrol consumption

Post by seasurfer »

Hiya, i get 35-38 mpg from my 2.8. I dont exactly drive him as enthusiatically as alot of you do, but i am very happy with my mpg (and i dont drive like a granny either) I have had my zed just over 3 years now and have checked the mpg consumption a few times properly and always had the same usage. (fill up, take mileage, long drive to yorkshire and back, fill up, take mileage and do the maths, only real way to check i think.
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Del
Joined: Sat 19 Nov, 2011 18:35
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  Z3 roadster 1.9

Re: petrol consumption

Post by Del »

tangomachine wrote:1.9 16v locally I get about 170-200 miles out of £40
SNAP for my 1.9 (M44) - at £1.39 per litre (UL locally here) that's about £6.32 per gallon.

I reckon I also get at least 200 from £40 which works out at just over 30 MPG. If people are getting nearly 40 MPG from the 2.8 I clearly bought the wrong car :(
seasurfer
Joined: Sat 22 Aug, 2009 13:02
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  Z3 roadster 2.2i
Location: South Lakes, Cumbria

Re: petrol consumption

Post by seasurfer »

On another thread on here last year when this question was asked, there were quite a few people getting 35 and over with their 2.8's :D
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billz
Joined: Mon 22 Mar, 2010 20:09
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  Z4 roadster 3.0si
Location: nottingham

Re: petrol consumption

Post by billz »

Well worth getting fault codes read. As a faulty sensor could be causing you to use more fuel. We have had tk replace the exhaust and now the inlet one has gone and on both occations mpg dropped to 21mpg

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Frank.A
Joined: Mon 20 Jul, 2009 21:15
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  Z3 roadster 2.8
Location: Twixt York and Hull

Re: petrol consumption

Post by Frank.A »

The 2.8 is generally accepted as the most economical.Mine averages around 33mpg but it once managed 40mpg in ideal conditions.
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Z3cade
Joined: Sat 09 Jan, 2010 18:18
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  M roadster S50
Location: Peterborough

Re: petrol consumption

Post by Z3cade »

My 3.2 averages 28mpg. And that's calculating between fill ups so spot on sums.
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dallantan
Joined: Mon 11 Jun, 2012 22:04
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Re: petrol consumption

Post by dallantan »

Z3cade wrote:My 3.2 averages 28mpg. And that's calculating between fill ups so spot on sums.
Are you ever off this website?

Do you have a job? Hahahahahhahaha
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Z3cade
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Location: Peterborough

Re: petrol consumption

Post by Z3cade »

dallantan wrote:
Z3cade wrote:My 3.2 averages 28mpg. And that's calculating between fill ups so spot on sums.
Are you ever off this website?

Do you have a job? Hahahahahhahaha
Same goes for you lately!!

Ill have you know I've changed the anti roll bar bushes on the polo thismorning and taken out our shower today!! Buzy buzy young man :wink:
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dallantan
Joined: Mon 11 Jun, 2012 22:04
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Re: petrol consumption

Post by dallantan »

Z3cade wrote:
dallantan wrote:
Z3cade wrote:My 3.2 averages 28mpg. And that's calculating between fill ups so spot on sums.
Are you ever off this website?

Do you have a job? Hahahahahhahaha
Same goes for you lately!!

Ill have you know I've changed the anti roll bar bushes on the polo thismorning and taken out our shower today!! Buzy buzy young man :wink:

Oh my days....not to change the topic toooo heavily but I have fed my cats and cleaned my garden! EVEN!!!
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Badman gee
Joined: Sun 14 Nov, 2010 10:45
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Re: petrol consumption

Post by Badman gee »

Gallons per mile for me,

:)
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Z3cade
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Location: Peterborough

Re: petrol consumption

Post by Z3cade »

Fed the cats?!.. Don't over do it! It's the weekend!

:wink:
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Z3cade
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Location: Peterborough

Re: petrol consumption

Post by Z3cade »

Badman gee wrote:Gallons per mile for me,

:)
Gallons per year...

The fuel in your Ms gone stale it's in that garage so long :wink:
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Badman gee
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Re: petrol consumption

Post by Badman gee »

Z3cade wrote:
Badman gee wrote:Gallons per mile for me,

:)
Gallons per year...

The fuel in your Ms gone stale it's in that garage so long :wink:
And it's staying there for a few more months.

Fitted my bonnet release today, it's great.

It's still out of fuel since our last trip Liam.
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Captain
Joined: Thu 28 Jun, 2012 06:43
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Location: Durban

Re: petrol consumption

Post by Captain »

I say drive it like you stole it, never mined the consumption :grin:

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Robert T
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  Z3 roadster 1.9
Location: Cheshire

Re: petrol consumption

Post by Robert T »

I thought Consumption was an old fashioned name for T.B.? Mine consumes petrol... I fill it up when it needs it... I've given up thinking about how much it costs. :wink:

Cheers R.
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r100elp
Joined: Sat 23 Feb, 2013 16:47
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  Z3 roadster 1.9

Re: petrol consumption

Post by r100elp »

ashford in kent to cairnryan 520 miles 36mpg in my 1.9
NOW the proud owner of a 98 1.9 M44 Z3 in silver.

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Southernboy
Joined: Thu 07 Oct, 2010 12:39
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Location: Johannesburg

Re: petrol consumption

Post by Southernboy »

When I hear the mileage / gallon the new cars are getting...100mpg !! with a 2lt motor, turbo, and 0-60 in a flash...makes me wonder how long can these new motors last....surely they'll be totalled within 5 years with those performances.
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Mike
Joined: Wed 14 Apr, 2004 10:53
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Location: la Gacilly, France
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Re: petrol consumption

Post by Mike »

Living in the UK south of London I used to get 26 to 28 mpg from my 2.8. Here in France I get 32 to 34 even though the driving is more spirited.
Main reason is traffic and no need here to drive miles in carparks finding a place. Just pull up outside the bar. Never more than 20 yards.
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John1950
Joined: Tue 15 Mar, 2011 18:49
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Location: Cadeilhan, Le Gers

Re: petrol consumption

Post by John1950 »

seasurfer wrote:Hiya, i get 35-38 mpg from my 2.8. I dont exactly drive him as enthusiatically as alot of you do, but i am very happy with my mpg (and i dont drive like a granny either) I have had my zed just over 3 years now and have checked the mpg consumption a few times properly and always had the same usage. (fill up, take mileage, long drive to yorkshire and back, fill up, take mileage and do the maths, only real way to check i think.

38mpg from a 2.8! :shock:
You must have feathers for legs.
Last summer I drove down to Croatia and back and covered about 3200 miles. I drove at a steady average of 70mph and then had a lot of local driving whilst on hol. By the time we got back to the front door having driven like an angel I got 34mpg so Christ knows how you get 38?
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TaffZee
Joined: Thu 20 May, 2010 09:45
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Re: petrol consumption

Post by TaffZee »

33mpg is the best I have got, and drove like a granny for the day, never went over 60mph.

Least I have had is 22mpg, that was on a cruise to the lakes organised by Billz.
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Del
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  Z3 roadster 1.9

Re: petrol consumption

Post by Del »

The figures in the 1997 BMW owner’s handbook are:-

1.9 (manual)
Urban – 24.8
Extra-urban – 47.1
Total – 35.3

2.8 (manual)
Urban – 20.3
Extra-urban – 38.7
Total – 29.1

3.2M
Urban – 17
Extra-urban – 35.8
Total – 25.4
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John1950
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Location: Cadeilhan, Le Gers

Re: petrol consumption

Post by John1950 »

Del wrote:The figures in the 1997 BMW owner’s handbook are:-

1.9 (manual)
Urban – 24.8
Extra-urban – 47.1
Total – 35.3

2.8 (manual)
Urban – 20.3
Extra-urban – 38.7
Total – 29.1

3.2M
Urban – 17
Extra-urban – 35.8

It's all lies!
Total – 25.4
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BladeRunner919
Joined: Fri 17 Feb, 2012 20:18
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  Z3 roadster 1.9

Re: petrol consumption

Post by BladeRunner919 »

I average 34mpg - that's a properly calculated figure based on use and miles between filling up.
Robin82
Joined: Fri 28 May, 2010 02:04
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  Z3 roadster 1.9

Re: petrol consumption

Post by Robin82 »

I'm currently doing a test. Cost me £65 to fill the tank... just over 48 litres of fuel. I am now down to half a tank (in a week) and the clock says 140 miles. :roll: I have a 1.9 and I'd be ok with 28 MPG. BUT I wish I knew that the 2.8 was more economical!!! :shock: Im now keeping my eyes pealed for a 2.8.
RichP
Joined: Wed 20 Feb, 2013 00:47
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  Z3 roadster 1.9

Re: petrol consumption

Post by RichP »

on my 1.9 it takes about £15 to get it from empty to 1/2 full, and then another £45 to get it to full. So sometimes i think i'm doing well, then it hits 1/2 way and plummets. once its at 1/4 i'm looking for a petrol station!
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BladeRunner919
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Re: petrol consumption

Post by BladeRunner919 »

Robin82 wrote:I'm currently doing a test. Cost me £65 to fill the tank... just over 48 litres of fuel. I am now down to half a tank (in a week) and the clock says 140 miles. :roll: I have a 1.9 and I'd be ok with 28 MPG. BUT I wish I knew that the 2.8 was more economical!!! :shock: Im now keeping my eyes pealed for a 2.8.
Don't go by the fuel gauge to judge whether you've used half a tank. They are notorious for bearing almost no relation to how much fuel is actually in the car. The only way to test how much has been used for certain is to refill the tank.

Every time I've seen a 1.9 vs 2.8 fuel economy discussion on a forum, the notion that the 2.8 is more economical is always debunked.
Mike Fishwick
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Location: Daglan, France

Re: petrol consumption

Post by Mike Fishwick »

Your cash/mileage figures do not make much sense, and are prone to innaccuracy - try filling up to the brim, using the tankful, and then refilling to the brim. Then just divide the miles by the volume (litres divided by 4.5) This is the ONLY way to get an accurate figure. Even the trip computer is about 10% optimistic, as it calculates at a rate of 5 litres per gallon. US market models are probably quite accurate, as it will work at 4 litres per gallon - just over a US gallon.

As already stated, it all depends on how and where you drive, and what kind of condition your car is in.

Half the BMWs I have worked on have pads which are rusted to their brackets, causing brake binding. It is easy enough to free them up and put a trance of CopaSlip etc on the sliding areas, but few people do it - instead, they think they have a sticky caliper and have a garage sell them new calipers . . . and discs . . . and pads!

I do not have to commute or do short runs in my 2.8, and drive with half a brain, finding that it usually returns 33-38 mpg, with the occasional 38/40 mpg day. After a puncture which wrecked a rear tyre I had to drive 520 miles on the emergency spare, which at 55/65 mph on autoroutes all the way worked out at 42 mpg.

Even an M Roadster, driven sensibly, can give 35 mpg - it's up to you, really. Given the same conditions and driving style, they all do about the same, but some owners appear to love boasting about how high a consumption their car has - as though it means that they are a really fast driver!
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John1950
Joined: Tue 15 Mar, 2011 18:49
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Location: Cadeilhan, Le Gers

Re: petrol consumption

Post by John1950 »

Mike Fishwick wrote:Your cash/mileage figures do not make much sense, and are prone to innaccuracy - try filling up to the brim, using the tankful, and then refilling to the brim. Then just divide the miles by the volume (litres divided by 4.5) This is the ONLY way to get an accurate figure. Even the trip computer is about 10% optimistic, as it calculates at a rate of 5 litres per gallon. US market models are probably quite accurate, as it will work at 4 litres per gallon - just over a US gallon.

As already stated, it all depends on how and where you drive, and what kind of condition your car is in.

Half the BMWs I have worked on have pads which are rusted to their brackets, causing brake binding. It is easy enough to free them up and put a trance of CopaSlip etc on the sliding areas, but few people do it - instead, they think they have a sticky caliper and have a garage sell them new calipers . . . and discs . . . and pads!

I do not have to commute or do short runs in my 2.8, and drive with half a brain, finding that it usually returns 33-38 mpg, with the occasional 38/40 mpg day. After a puncture which wrecked a rear tyre I had to drive 520 miles on the emergency spare, which at 55/65 mph on autoroutes all the way worked out at 42 mpg.

Even an M Roadster, driven sensibly, can give 35 mpg - it's up to you, really. Given the same conditions and driving style, they all do about the same, but some owners appear to love boasting about how high a consumption their car has - as though it means that they are a really fast driver!
Mike, does that mean all the Zed's trip computers are calibrated to US gallons/miles - even the export models such as ours?
Above I quoted my last summer Croatia holiday consumption from the trip computer so this year I think I'll make the effort to do actual litres put in against miles to get a more accurate picture - at least then I'll know what the error factor is with the trip computer.
John Walker
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Mike Fishwick
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Location: Daglan, France

Re: petrol consumption

Post by Mike Fishwick »

No - as I remarked: Even the trip computer is about 10% optimistic, as it calculates at a rate of 5 litres per gallon. US market models are probably quite accurate, as it will work at 4 litres per gallon - just over a US gallon.

I find that my (UK) trip computer is about 10% optimistic, as it must be programmed at whole numbers of litres per gallon, or in our case a rate of 5 litres per gallon. The US models would be quite accurate due to their smaller gallon (one of their quarts being just under a litre) at 4 litres per gallon.

By filling to the brim and calculating the consumption over a tankful of fuel, it is easy enough to check, but it seems a pity to spoil the good news!
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stupot50
Joined: Tue 07 Aug, 2012 08:35
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Location: Torquay, Devon

Re: petrol consumption

Post by stupot50 »

If i go by my computer, I'm only getting 13.2mpg around the streets of Torquay :?
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BladeRunner919
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Re: petrol consumption

Post by BladeRunner919 »

I believe the OBC fuel consumption can be recalibrated to your car's actual measured average usage.

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John1950
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Location: Cadeilhan, Le Gers

Re: petrol consumption

Post by John1950 »

BladeRunner919 wrote:I believe the OBC fuel consumption can be recalibrated to your car's actual measured average usage.

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Does anyone know what these 'correction factors' relate to and how I might use them?
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BladeRunner919
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Re: petrol consumption

Post by BladeRunner919 »

Well, my understanding (and I don't have an OBC, so can't test this) is that you need to reset the MPG on the OBC, then calculate your actual consumption over the next couple of tanks of fuel, then compare that to what the OBC has recorded over those same tanks of fuel.

You then need to find out what the setting in Test 3 is currently set to, then calculate a new value for it by using:

new_value = old_value *(actual_mpg / obc_mpg)

Enter that value, and it should alter the MPG calculation to match the car's actual. I guess you then reset the MPG and test it again over a couple of tanks of fuel.
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John1950
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Location: Cadeilhan, Le Gers

Re: petrol consumption

Post by John1950 »

BladeRunner919 wrote:Well, my understanding (and I don't have an OBC, so can't test this) is that you need to reset the MPG on the OBC, then calculate your actual consumption over the next couple of tanks of fuel, then compare that to what the OBC has recorded over those same tanks of fuel.

You then need to find out what the setting in Test 3 is currently set to, then calculate a new value for it by using:

new_value = old_value *(actual_mpg / obc_mpg)

Enter that value, and it should alter the MPG calculation to match the car's actual. I guess you then reset the MPG and test it again over a couple of tanks of fuel.

That's lost me already.
So, it seems I must have some external, plugged in keyboard device to enable text input?
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Robert T
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Location: Cheshire

Re: petrol consumption

Post by Robert T »

Arctic Silver '99 Z3 1.9 & Black '59 Frogeye 1275cc
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DC
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Location: Inverness-shire

Re: petrol consumption

Post by DC »

Over around 11000 miles of use I've averaged just over 35 mpg.
It can only be checked accurately by brimming the tank, zeroing milometer and recording gallons used per fill.
Not much traffic around these parts so that probably helps quite a bit along with Summer use only.
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BladeRunner919
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Re: petrol consumption

Post by BladeRunner919 »

John1950 wrote: That's lost me already.
So, it seems I must have some external, plugged in keyboard device to enable text input?
No. If you look at the document it explains how you use the buttons on the OBC to access and change the values.
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John1950
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Re: petrol consumption

Post by John1950 »

Robert T wrote:This post may help:

http://forums.bimmerforums.com/forum/sh ... he-OBC-MPG

Cheers R.

Thanks Robert, I'll copied that lot into a Word doc - I'll have a look at it once we get some sunshine. the Zed's currently still under wraps in the garage.
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Mike Fishwick
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Location: Daglan, France

Re: petrol consumption

Post by Mike Fishwick »

The information on trimming the mpg readout was very interesting - you learn something every day! I'l go and try it now. I guess the 750 to 1250 range is a plus and minus 0.25 correction.

The fuel consumption figures given in the handbook relate to a particular DIN usage cycle, and cannot be related to any individual driving style. In general, the extra-urban figure is whatyou can expect in normal driving without commuting or town driving, but like all these figures, it can be better or worse depending on the driving style and the exact conditions - it is not Holy Writ!

Other factors affecting fuel consumption are:

(a) Fuel type and make - 97 octane (if you can find any in the UK, particularly in the south) will give better mpg than 95, and on my visits to the UK I find that in terms of fuel consumption Esso 95 is the best of the bunch. Shell V P{ower and BP Ultimate are disappointing, and Tesco Millenium likewise.

(b) Tyre pressures - increased pressures give lower rolling resistance, and up to a point better grip/handling. I find 2.4 bars F & R to give the optimum on Falken FK-452 on 17 inch wheels.

(c) Maintenance - partially-clogged air filters, old engine oil, and worn plugs all do their bit, and binding brakes are the worst culprit.

(d) Remember that at motorway-type speeds, having the roof down will cost about 10% off your mpg.

(e) Remapping will usually make small a improvemens to torque and therefore to mpg.

(f) Driving style - Avoid cold running, or worse still, uneccessary idling when cold. Just because it is a sports car you are not obliged to use peak revs - particularly when cold - and keep booting the throttle. Heavy braking is a sign of fuel having been wasted in unneccessary acceleration. There are other ways to enjoy your driving, such as improving your anticipation of having to slow down. Use as little throttle as you can, but use downhill runs to help pick up speed for the next hill. Do not use a cruise control - the invention of the Devil and the Americans - as these cannot anticipate, and will keep to a set speed downhill, then open the throttle wider for the uphill sections of road.
A Z3 is not just for Christmas - it's for life!
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John1950
Joined: Tue 15 Mar, 2011 18:49
Posts: 655

  Z3 roadster 2.8
Location: Cadeilhan, Le Gers

Re: petrol consumption

Post by John1950 »

Mike Fishwick wrote:The information on trimming the mpg readout was very interesting - you learn something every day! I'l go and try it now.

Other factors affecting fuel consumption aer:

(a) Fuel type and make - 97 octane (if you can find any in the UK, particularly in the south) will give better mpg than 95, and on my visits to the UK I find that in terms of fuel consumption Esso 95 is the best of the bunch. Shell V P{ower and BP Ultimate are disappointing, and Tesco Millenium likewise.

(b) Tyre pressures - increased pressures give lower rolling resistance, and up to a point better grip/handling. I find 2.4 bars F & R to give the optimum on Falken FK-452 on 17 inch wheels.

(c) Maintenance - partially-clogged air filters, old engine oil, and worn plugs all do their bit, and binding brakes are the worst culprit.

(d) Remember that at motorway-type speeds, having the roof down will cost about 10% off your mpg.

(e) Remapping will usually make small a improvemens to torque and therefore to mpg.

(f) Driving style - Avoid cold running, or worse still, uneccessary idling when cold. Just because it is a sports car you are not obliged to use peak revs - particularly when cold - and keep booting the throttle. Heavy braking is a sign of fuel having been wasted in unneccessary acceleration. There are other ways to enjoy your driving, such as improving your anticipation of having to slow down. Use as little throttle as you can, but use downhill runs to help pick up speed for the next hill. Do not use a cruise control - the invention of the Devil and the Americans - as these cannot anticipate, and will keep to a set speed downhill, then open the throttle wider for the uphill sections of road.
Mike
Your remark about the cruise control is interesting. In Britain, road discipline and manners are so bad that cruise control is virtually useless anyway, but I'd pretty much come to the same conclusion myself after many miles of long continental driving - not that my Zed has it fitted anyway.
I changed my engine oil about this time last year and the cars only done about 4000 miles since then and has been in the garage since the beginning of November. I often wonder if oil degrades by not getting used and just sitting in a sump for months? Certainly I must look at the air filter again as soon as the sun returns, check tyre pressures (I hope there's no flat spots) but re-mapping isn't likely to happen.
Oh, and one final thing, perhaps I should start putting in quality fuel rather than the standard supermarket stuff - maybe even some fuel system cleaner (was it Red X I used to see in garages?).
John Walker
Baarn, Holland
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Mike Fishwick
Joined: Fri 19 Jun, 2009 10:27
Posts: 2093

  Z3 roadster 2.8
Location: Daglan, France

Re: petrol consumption

Post by Mike Fishwick »

In Belgium new cars are not permitted to have a cruise control fitted, and any tourist found using one can be fined - true civilisation! As in the UK, they cause more congestion than anything else - but of course the average Brit loves nothing better than a good queue. As you say, road conditions in the UK are unsuitable for cruise control use - but so many people use them. Some try to get past you by about half an MPH, or are too lazy to turn them off, and belt up behind someone, using the brakes at the last moment.

Oil usually degrades by carrying carbon particles and moisture, but for most people a synthetic oil will last all year.

On the subject of Redex, Opie Oils, who should know a thing or two about lubrication, say that you may as well use a teaspoon of engine oil! They suggest that a good synthetic two-stroke oil is far better, but in the long term it may harm your catalyic converter.

I forgot to add that living in France I have ready access to decent 98 octane fuel, which gives me about 10% better mpg for only another 3% price above 95 octane, which is a cheap advantage. It makes one wonder why it costs so much more - if you can get it - in the UK.



Anyway - I just tried the above instruction on my trip computer, and found a couple of small differences from the guide above.

I found that all 5 functions can be adjusted - this is what I did to hopefully redice my mpg reading by 10% - I'll report back when I find the optimum value.


(1) Set ignition switch to position 2

(2) Press Set/Reset and Clock simultaneously to enter service mode – display reads 1

(3) Press stalk switch to reach required function 1 to 5:
1 – 12/24 hour operation
2 - Display test – all segments operate
3 – MPG adjustment
4 – Acoustic warning test
5 – Temperature indication in F or C

(These functions are adjusted by the Clock button, and stored by the Set/Reset button.)


I selected option 3 to trim the fuel consumption reading.

(4) Press and hold Clock, then press Set/Reset and release both buttons.

(5) Display reads (factory set) 1000

(6) Press Clock to change reading upwards to 1250. Keep pressing to reach 750 and count upwards. For a 10% reduction in reading I set at 900.

(7) Press Set/Reset to save new setting.

(8) Turn off ignition to return to normal operation.
A Z3 is not just for Christmas - it's for life!
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Deano1712
Z Register organiser
Joined: Sat 05 Aug, 2006 12:56
Posts: 1396

  M roadster S50
Location: Leeds

Re: petrol consumption

Post by Deano1712 »

My Z3 returns 20mpg is driven carefully and 14mpg if driven hard :roll:
Z3M with a few mods...and a little bit more power
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