50mpg

[mickmull]

Had a run through the North York Moors of around 90 minutes and nursed the gearbox of our California (150hp manual) in variable traffic but mostly in the 40- 60mph zone, certainly not hanging about - and managed to return of over 50mpg on the computer - Ok I know that the computers are not perfect at fuel consumption but they do give a guideline. Didn't hold up any traffic either...

So

lets have some mpg stories!

 

[sidepod]

I definitely get some

 

[pjm-84]

118.6mpg for the last 4500miles since its service last December (buggers always reset the history) or 66.8mpg for the first 5122miles on the CHR (drove it tonight as I had to fill it up) . To compensate the V8 being doing about 17mpg.

 

[Wildcamper]

Was that all down hill?

 

[mickmull]

100 mpg ? Outstanding - always thought that the MPG thing was linked to the ECU running the engine - but I guess it may be estimate!

 

[Calimili]

100 mpg ? Outstanding - always thought that the MPG thing was linked to the ECU running the engine - but I guess it may be estimate!

100+ mpg? Why bother with electric vehicles .

 

[Wildcamper]

Can't do 50 mpg. Over 20,000 miles have averaged 37mpg. Best ever on one tank was 43. T6, LWB 150 DSG.

 

[Louis II]

Was that all down hill?

Or being towed?

 

[pjm-84]

Not charging all the time and a few trips to London dropped the average down. Does about 40-42mpg on a flat battery. Not my car but a stock photo. (Not a car you are really too bother to photograph)

 

[Jay20cali]

Fully loaded up inc full tank of water and fuel plus 3bikes on the bike rack 38.1 mpg will definitely miss this when we get our crafter/Man Westfalia

 

[Amarillo]

Four times I have managed over 40 mpg on brim to brim measurements recorded on the "Road trip" app.

Refill 13 March 2018: 1009 Km, 71.16 Litres, 40.05 mpg, fully laden with four bikes on back

Two refills 13/16 April 2018: total 1422 Km, 99.01 Litres, 40.57 mpg, fully laden plus four bikes

Refill 28 June 2018: 1062 Km, 74.12 Litres, 40.47 mpg.

Refill 26 November 2018: 1083 km, 73.39 Litres, 41.69 mpg.

My record on the MFD on 11 January 2018, before I started using the "road trip" app to record fuel consumption, was 18.2 km/l which equals 51.4 mpg over a single 638 km run about half on Sicily's empty motorways.







The brim to brim measurement was 16.43 Km/l or 46.4 mpg.

 

[mickmull]

Think our overall average is around 38 - 40 mpg - just had a good run yesterday. Just shows you how frugal these things can be on the right road and speed combination. Going to have to try not to become addicted to watching the av consumption read out...

 

[GSX1300R]

Ours consistently did around 36 ish..Tank full to full not computer. have just had it remapped and done around 800 miles some motorway some town and now get 41.Full to full...also less gear changes.Cant see how I could possibly get any better driving like a vicar...

 

[Amarillo]

Think our overall average is around 38 - 40 mpg - just had a good run yesterday. Just shows you how frugal these things can be on the right road and speed combination. Going to have to try not to become addicted to watching the av consumption read out...

The MFD consistently overreads when compared to brim-to-brim measurements.

 

[Velma's Dad]

The MFD consistently overreads when compared to brim-to-brim measurements.

That's no surprise then.

 

[mickmull]

Think either way has its issues... Not sure how accurate a pump is and I tend not to check the ambient temperature that my fuel is delivered at from the pump!

Thought the MFD feature was a by-product of fuel injection computers, so rather than measuring your tank and how many miles, they count the duration and number of injection pulses, hence fuel being used. That's why you can get a 'range' feature too. My MKII Golf GTI had that on. Guess if MFD mileage is wildly out may point to an injection or fueling issue... Someone on here will know how it works.

 

[WelshGas]

Think either way has its issues... Not sure how accurate a pump is and I tend not to check the ambient temperature that my fuel is delivered at from the pump!

Thought the MFD feature was a by-product of fuel injection computers, so rather than measuring your tank and how many miles, they count the duration and number of injection pulses, hence fuel being used. That's why you can get a 'range' feature too. My MKII Golf GTI had that on. Guess if MFD mileage is wildly out may point to an injection or fueling issue... Someone on here will know how it works.

The MFD won't take account of diesel usage in the Parking Heater or the Webasto Engine Coolant Heater.

 

[mickmull]

Good point there WelshGas! The MFD will read diesel going into the engine and miles covered. If you do a 'tank to tank' check and run the diesel heater all night then it may seem you are getting poor MPG!

 

[Velma's Dad]

Never understood the obsession with mpg, once you own the vehicle in question. It'll use whatever it uses and you have to fill it up when it's empty.

Ye don't fatten yon pig by weighing 'un, young-un.

 

[Amarillo]

Good point there WelshGas! The MFD will read diesel going into the engine and miles covered. If you do a 'tank to tank' check and run the diesel heater all night then it may seem you are getting poor MPG!

I have 30 months of detailed consumption both from the MFD and brim-to-brim. The MFD nearly always overreads MPG.

Date	brim to brim	MFD
4 Sept 20	33.39	34.7	+3.9%
19 Aug 20	39.18	38.1	-2.8%
8 Aug 20	33.7	35.1	+4.2%
18 Jul 20	33.12	35	+5.7%
3 Jul 20	32.35	32.9	+1.7%
14 Jun 20	35.37	37.5	+6%
26 May 20	36.07	38.1	+5.2%
9 May 20	33.84	36.7	+8.6%
14 Mar 20	32.17	34.3	+6.6%
21 Feb 20	34.33	35.4	+3.1%
18 Feb 20	36.89	38.0	+3%
1 Feb 20	33.14	36.4	+9.8%
2 Jan 20	30.1	32.9	+9.3%
7 Dec 19	37.92	39.9	+5.2%
19 Nov 19	32.12	34.4	+7.1%
21 Oct 19	34.24	No record
22 Sept 19	35.06	38.1	+8.7%
31 Aug 19	35.1	36.7	+4.6%
20 Aug 19	31.04	32.5	+4.9%
16 Aug 19	37.15	38.9	+4.7%
4 Aug 19	30.56	33.2	+8.6%
18 Jul 19	28.25	31.1	+10.1%
25 Jun 19	28.07	30.9	+10.1%
12 Jun 19	34.8	36.8	+5.7%
1 Jun 19	36.23	37.9	+4.6%
25 May 19	30.26	31.1	+2.8%
23 May 19	29.22	29.4	+0.6%
16 May 19	27.87	31.8	+14.1%
16 Apr 19	33.23	37.1	+11.5%
5 Apr 19	26.11	29.4	+12.6%
16 Mar 19	35.84	40.5	+13%

Notes:

1. The overreading of the MFD does appear to be worse in winter months when the heaters are being used. Evidence of this is weak.
2. In July 2019 we bought a city car as a second car. This is predominantly used for short trips. The overreading in the MFD was far worse when Amarillo was our only vehicle. Further supporting this hypothesis is that during late May and Early June 2019 when the MFD appears comparatively accurate Amarillo went on a return trip to northern Spain. Evidence of increased accuracy for longer journeys is reasonably strong.

 

[Amarillo]

Never understood the obsession with mpg

Often the first evidence that something is wrong with the engine.

 

[mickmull]

Crumbs Amarillo! That's a detailed record.

Looking through I would expect the MFD to 'over read' when using the heater. Your figures will give you a lower tank to tank mileage if some of the diesel is being used to keep you toasty - whereas the MFD should be reading what goes into the engine for the miles you've done.

I guess not all the energy from the combustion of diesel in the engine goes to pushing you down the road, and in winter more is used for auxiliaries plus engine oil takes longer to warm up and all that sort of thing. Short journeys are not very efficient in any car I don't think.

Guess on a longer run the batteries are charged, the engine warm, and in northern Spain you may not have the heated seats running!

Think I may switch mine to show what radio station is playing and not worry about the mpg!

 

[WelshGas]

Often the first evidence that something is wrong with the engine.

There is a difference between Observing and Obsession with regards to MPG.
As long as mine is in the ballpark I just drive and fill.

 

[Velma's Dad]

Often the first evidence that something is wrong with the engine.

With modern vehicles I'd pay much more attention to the ECU microprocessor and any warnings it throws from its million+ lines of code continuously analysing dozens of sensors including:
- Fuel flow
- Air mass flow
- Manifold pressure
- Intake air temp
- Oxygen level
- Throttle position
- Crankshaft speed
- Whether car is connected to an emissions test rig (VW special option).

And with older cars... well all I can say is in 40+ years I've never detected a fault by monitoring fuel consumption and spotting any changes. Clattering noises from the front, smoke in the real view mirror, pool of oil spreading gently over the road, yes.

 

[Amarillo]

Crumbs Amarillo! That's a detailed record.

I use an app called “Road trip”. All I do is tap in the odometer, refuel and MFD(2) numbers and the app does the rest.