m44 mpg

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littlefeller
Joined: Sun 28 Apr, 2013 18:06
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m44 mpg

Post by littlefeller »

ok, what is everyone elses average mpg for the 1.9 m44? mine is 37-40mpg suggesting my o2 sensor is fine, though inpa says otherwise, though this could be down to a hole in the exhaust.
Keynun
Joined: Wed 15 Aug, 2012 17:02
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  Z3 roadster 2.8

Re: m44 mpg

Post by Keynun »

I used to get around 25mpg on the trip computer on my old car (1999 m44 e36 coupe). This was after I replaced the o2 sensor. This was in London though.
GE45TON
Joined: Sun 29 Apr, 2012 18:32
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  Z3 roadster 1.9

Re: m44 mpg

Post by GE45TON »

Sounds about right, I get just on 300 miles from a tank on a run. You can use GunGum exhaust bandage if it's one of the pipes rather than the box and as long as it seals the hole then it's not an MOT failure.
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BladeRunner919
Joined: Fri 17 Feb, 2012 20:18
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  Z3 roadster 1.9

Re: m44 mpg

Post by BladeRunner919 »

GE45TON wrote:Sounds about right, I get just on 300 miles from a tank on a run. You can use GunGum exhaust bandage if it's one of the pipes rather than the box and as long as it seals the hole then it's not an MOT failure.
If you get 300 miles from a tank, that means you're getting about 27mpg.

I get about 35 mpg, mostly commuting without any significant long motorway runs. That's a properly calculated figure based on actual usage and distance travelled.
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BladeRunner919
Joined: Fri 17 Feb, 2012 20:18
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  Z3 roadster 1.9

Re: m44 mpg

Post by BladeRunner919 »

Keynun wrote:I used to get around 25mpg on the trip computer on my old car (1999 m44 e36 coupe). This was after I replaced the o2 sensor. This was in London though.
Trip computers need calibrating to the car, so unless you measured actual usage and mileage, trip computer reading are meaningless.
littlefeller
Joined: Sun 28 Apr, 2013 18:06
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Re: m44 mpg

Post by littlefeller »

mine is calculated by the odometer, coupled with the fact I know exactly how far I drive to work as I double checked on google earth. I don't really do much town driving, its just over 13 miles along b roads to where I work, there are quite a few 40 zones and 50 zones so no real speeding as such (I don't really do that kind of thing any more as im getting older and wiser, though I do still corner faster than most). the hole was picked up in my last mot, but was just an advisory, it also failed the emissions test but it didn't appear on the mot retest (it failed on a ball joint originally). inpa says there is a fault with the o2 sensor, but engine pulls as normal and mpg seems fine. I will try blocking the hole first and see if it makes any difference.

I always put 9.08 litres in as that is 2 gallons, rest the odometer, then drive till the light comes on, furthest I have dared drive with the light on is 56 miles :shock: is this a record :lol:
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BladeRunner919
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  Z3 roadster 1.9

Re: m44 mpg

Post by BladeRunner919 »

My light comes on at 315miles on the odometer, and I reckon my range of a full tank is 398 miles, so in theory I could! But I don't think I'd necessarily try it!
littlefeller
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Re: m44 mpg

Post by littlefeller »

hey that's good, then in theory I could go till I see 83 miles :)
gIzzE
Joined: Mon 06 Aug, 2007 21:32
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Re: m44 mpg

Post by gIzzE »

littlefeller wrote: I always put 9.08 litres in as that is 2 gallons, rest the odometer, then drive till the light comes on, furthest I have dared drive with the light on is 56 miles :shock: is this a record :lol:

That's a pretty poor way to work out your MPG.

Fill up from a pump to the first click, then drive it till the light comes on and fill again from the same pump till the first click and then work it out.

Over 9 litres you could be up to 20% out on your calcs.

I get around 32mpg from my 2.8i, last tank was 35mpg.
GE45TON
Joined: Sun 29 Apr, 2012 18:32
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  Z3 roadster 1.9

Re: m44 mpg

Post by GE45TON »

BladeRunner919 wrote:
GE45TON wrote:Sounds about right, I get just on 300 miles from a tank on a run. You can use GunGum exhaust bandage if it's one of the pipes rather than the box and as long as it seals the hole then it's not an MOT failure.
If you get 300 miles from a tank, that means you're getting about 27mpg.

I get about 35 mpg, mostly commuting without any significant long motorway runs. That's a properly calculated figure based on actual usage and distance travelled.

yes you're right, :oops:
should have said that's before the warning light comes on. When I calculate the distance and fuel used then it's about 37, give or take. A bit less when I'm just out for a spin...

:)
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lightning
Joined: Tue 27 Nov, 2007 08:15
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  Z3 roadster 3.0i
Location: Stockport

Re: m44 mpg

Post by lightning »

On my 3.0 the trip computer claims l am achieving 35-40mpg.

This is clearly lies.

I put in £20 Super Unleaded, which is about three gallons, and it did 80 miles. That's about 27 mpg which is probably about right. (round town driving and short journeys)

It might do 35-40mpg on a motorway run. But the trip computer is like a BBC weather forecast.....untrue.
gIzzE
Joined: Mon 06 Aug, 2007 21:32
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  Not specified

Re: m44 mpg

Post by gIzzE »

You can tell **** all over £20.

Fill it up, reset the obc and use a whole tank, then work it out.
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lightning
Joined: Tue 27 Nov, 2007 08:15
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  Z3 roadster 3.0i
Location: Stockport

Re: m44 mpg

Post by lightning »

I can tell how many miles it's done when the low fuel warning light comes back on......80

But yes, l know what you are getting at. A full tank will take in more varied driving, such as motorway trips etc, and so give a more accurate overall MPG.
littlefeller
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Re: m44 mpg

Post by littlefeller »

gIzzE wrote:
littlefeller wrote: I always put 9.08 litres in as that is 2 gallons, rest the odometer, then drive till the light comes on, furthest I have dared drive with the light on is 56 miles :shock: is this a record :lol:

That's a pretty poor way to work out your MPG.

Fill up from a pump to the first click, then drive it till the light comes on and fill again from the same pump till the first click and then work it out.

Over 9 litres you could be up to 20% out on your calcs.

I get around 32mpg from my 2.8i, last tank was 35mpg.
think I need to clarify, I don't reset the odometer when I fill, I reset it when the light comes on. so I drive till light on, (usually around 20 miles with light on as there are no petrol stations on my way to work) then I reset the odometer, then put 2 gallons in and drive till light on again, with spirited cornering it does sometimes trick the fuel gauge warning light into coming on early, so I drive real carefully when it gets close to coming on.
gIzzE
Joined: Mon 06 Aug, 2007 21:32
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  Not specified

Re: m44 mpg

Post by gIzzE »

You don't need to clarify, you need to understand that the light can come on with anywhere between 8-11 litres left in the tank depending on how it is sitting in the tank.
Then driving 'around' 20 miles to you reach a filling station and trying to work out what you are getting mpg wise from that is pointless.

Fill the car up full, either first click of the pump or till you can no longer get any more in the filler neck, you will see the fuel down the neck, it will be the same distance as the pump nozzle is long.

then reset your odo and obc and drive till you are low and fill back up.

Write down how much fuel was needed to get back to the same fill level and how many miles you did, that will give you a pretty accurate figure.

The way you are doing it is pointless.
Cooper01
Joined: Tue 29 Apr, 2014 08:06
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  Z3 roadster 3.0i

Re: m44 mpg

Post by Cooper01 »

gIzzE wrote:You don't need to clarify, you need to understand that the light can come on with anywhere between 8-11 litres left .......The way you are doing it is pointless.
Agreed. Use actual figures as per above. It is the only accurate way.
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BonBon
Joined: Tue 08 Jan, 2008 21:10
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Re: m44 mpg

Post by BonBon »

37-40 MPG?
What do you get when you go uphill? :lol:
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lightning
Joined: Tue 27 Nov, 2007 08:15
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Location: Stockport

Re: m44 mpg

Post by lightning »

You can thank me for the warmer Summer this year.
My Ferrari Mondial t did 14mpg.

I once put £100 of petrol in it in one day of local driving. You could almost see the birds falling out of the trees from the fumes as you drove past.
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BladeRunner919
Joined: Fri 17 Feb, 2012 20:18
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  Z3 roadster 1.9

Re: m44 mpg

Post by BladeRunner919 »

lightning wrote:You can thank me for the warmer Summer this year.
My Ferrari Mondial t did 14mpg.
I used to dream of 14mpg when I had a Range Rover as a daily driver. Thank goodness for LPG!
therealdb1
Joined: Tue 25 Jun, 2013 21:47
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  Z3 roadster 2.0

Re: m44 mpg

Post by therealdb1 »

My supercharged Jag used to struggle to reach 14mpg on a run!
Cyclists saving the planet pretended to choke on the fumes as it wafted past.
It was a very fast motor car by any standards but unfortunately Jaguar forgot to fit any brakes!

The consensus is correct on working out mpg though. The more miles /fuel you calculate over the better because you are reducing your 'measurement uncertainty'. A small error is proportionately larger on 2 gallons than it is on 20 gallons so a complete tankful is the bare minimum you should consider to test your mpg figures.
I used to have an Excel spreadsheet set up (sad I know!) for all of my vehicles and updated it at each fill up. This calculated the mpg for the previous fill and a continuous mpg over the years. Keeping a long term eye of fuel consumption can be quite useful to indicate potential problems before symptoms become obvious.
I only gave up this schedule because I drive so few miles these days, maybe 2500 per year if that.
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akirk
Joined: Fri 20 Apr, 2012 08:11
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  Z3 roadster 3.0i

Re: m44 mpg

Post by akirk »

lightning wrote:You can thank me for the warmer Summer this year.
My Ferrari Mondial t did 14mpg.

I once put £100 of petrol in it in one day of local driving. You could almost see the birds falling out of the trees from the fumes as you drove past.
only £100 :)

I once filled my jag and my range rover twice each in the same day - total of 80 gallons of petrol
the jag was the more economical at 20mpg, the RR did 17 on a good day, 15 normally and 4 once!

Alasdair
gIzzE
Joined: Mon 06 Aug, 2007 21:32
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  Not specified

Re: m44 mpg

Post by gIzzE »

Fillled up the ML350 yesterday and that was £130.
But it does 26mpg so you don't have to go every day! :?


The only car I have ever owned that was really poor on mpg was my S4 avant, the V8, it would do 16-19mpg every tankful no matter what.

The CSL could do single digit figures as well, but on the roads even when pressing on it would always end up just over 20mpg.
littlefeller
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Re: m44 mpg

Post by littlefeller »

only got 35 today :evil: but I did do some town possing over the weekend :twisted: yes I understand about the light, if I corner too fast it comes on early (or going up a steep hill) :evil: but it has been pretty consistent so far, been doing this for 6 weeks now.
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