Prius Mk 4 Mpg

[nellsey]

An update.

I have now done 1500 miles in my new Mk 4 at an average of 68mpg. Fantastic economy.

 

 

 

 

[barrycoll]

With just 512 miles on the clock, the tank took 35.9 litres, and so shows 64.8mpg

So possibly 7 litres left in the tank, and distance-to-empty suggesting 70 miles

It is surprising just how quickly 65 mpg doesn't seem "enough' and there is a lust for a magic 70!!  

....maybe...with warmer temps and a looser engine?

 

 

 

[birdseye]

Is that all your getting, mine beats you all

[Chris Dance]

I have 650 miles on the clock and after a 70 mile run mainly on country roads today consumption on MFD showed 73 MPG.

[nellsey]

It seems as if I need to up my game

[barrycoll]

Brim to brim fill up only folks.....display mileage not counted!!!!

[nellsey]

On 17/04/2017 at 6:02 PM, barrycoll said:

Brim to brim fill up only folks.....display mileage not counted!!!!

Thats not as much fun!

I wonder how far out the suggested MPG is?

[PeteB]

3 hours ago, nellsey said:

...I wonder how far out the suggested MPG is?

I use a database app on my phone to log all fuel and mileages, and it shows the error in mpg and percent.  Here is an extract, which I hope will stay usefully formatted.

Date	Rdg	Dist	Litres	Cost	p/ml	Actual MPG	Car display  mpg	mpg diff	mpg error %	Gals	Gals Left	£/Gal	£/ltr	Car Range Est	Days	EV%
12/06/2016	131	131	10.09	11.39	8.69	59.01	73.5			2.22	7.24	5.13	1.13
22/06/2016	733	602	38.72	42.55	7.07	70.66	74.2	-3.54	-5.01	8.52	0.94	4.99	1.10	8	10	48
04/07/2016	1328	595	38.44	41.86	7.04	70.33	74.3	-3.97	-5.64	8.46	1.00	4.95	1.09	30	12	50
15/07/2016	1921	593	38.57	44.32	7.47	69.93	75.3	-5.37	-7.68	8.48	0.98	5.23	1.15	9	11	47
29/07/2016	2502	581	40.31	44.30	7.62	65.50	71.4	-5.90	-9.01	8.87	0.59	4.99	1.10	2	14	53
13/08/2016	3106	604	40.00	42.36	7.01	68.64	72.9	-4.26	-6.21	8.80	0.66	4.81	1.06	16	15	56
22/08/2016	3729	623	40.25	42.54	6.83	70.40	74.9	-4.50	-6.39	8.85	0.61	4.81	1.06	4	9	43
05/09/2016	4284	555	38.78	41.77	7.53	65.06	69.5	-4.44	-6.82	8.53	0.93	4.90	1.08	33	14	54
17/09/2016	4854	570	38.45	41.49	7.28	67.38	70.5	-3.12	-4.63	8.46	1.00	4.90	1.08	27	12	50
30/09/2016	5400	546	37.38	40.71	7.46	66.42	71.5	-5.08	-7.65	8.22	1.24	4.95	1.09	50	13	49
10/10/2016	5952	552	37.74	41.40	7.50	66.51	71.0	-4.49	-6.75	8.30	1.16	4.99	1.10	20	10	34
20/10/2016	6525	573	39.68	44.40	7.75	65.64	71.3	-5.66	-8.62	8.73	0.73	5.09	1.12	8	10	38
31/10/2016	7090	565	39.10	44.46	7.87	65.70	71.0	-5.30	-8.07	8.60	0.86	5.17	1.14	28	11	38
16/11/2016	7595	505	38.31	42.87	8.49	59.91	63.2	-3.29	-5.49	8.43	1.03	5.09	1.12	20	16	46
30/11/2016	8104	509	38.11	42.19	8.29	60.74	65.4	-4.66	-7.67	8.38	1.08	5.03	1.11	34	14	50
12/12/2016	8607	503	35.65	40.61	8.07	64.16	66.8	-2.64	-4.11	7.84	1.62	5.18	1.14	44	12	44
24/12/2016	9104	497	37.96	43.24	8.70	59.52	64.1	-4.58	-7.69	8.35	1.11	5.18	1.14	22	12	41
16/01/2017	9577	473	38.13	44.50	9.41	56.38	60.4	-4.02	-7.13	8.39	1.07	5.30	1.17	25	23	46
28/01/2017	10079	502	38.93	45.90	9.14	58.64	63.9	-5.26	-8.97	8.56	0.90	5.36	1.18	22	12	31
14/02/2017	10574	495	36.80	43.02	8.69	61.11	63.6	-2.49	-4.07	8.10	1.36	5.31	1.17	42	17	47
23/02/2017	11101	527	37.09	43.36	8.23	64.58	69.9	-5.32	-8.24	8.16	1.30	5.31	1.17	42	9	34
09/03/2017	11600	499	37.26	43.93	8.80	60.85	65.2	-4.35	-7.15	8.20	1.26	5.36	1.18	42	14	44
23/03/2017	12139	539	38.38	44.48	8.25	63.86	67.8	-3.94	-6.17	8.44	1.02	5.27	1.16	11	14	44
08/04/2017	12647	508	36.97	42.11	8.29	62.48	66.7	-4.22	-6.75	8.13	1.33	5.18	1.14	39	16	43
17/04/2017	13184	537	37.70	43.32	8.07	64.78	70.1	-5.32	-8.21	8.29	1.17	5.23	1.15	43	9	35

[barrycoll]

Interestingly, between 2 to 7 mpg difference between actually, and displayed.

Maybe not quite brim to brim...perhaps Pete????

I noticed at the weekend that the car will go into EV mode while using RCC, at about 65 mph.

The Gen 4 is showroomed as 122 bhp in total, but the brochure for the Gen 3 (still in my file) only gives the ICE as 99 bhp, and no total....

................but the Auris is 136 bhp????

[PeteB]

4 hours ago, barrycoll said:

...Maybe not quite brim to brim...perhaps Pete????

I noticed at the weekend that the car will go into EV mode while using RCC, at about 65 mph...

I always brim to the same level to the best of my ability - maybe warmer or cooler weather has an effect? (expansion of fluids) - just the last drop out of the pump nozzle, a tiny drop  tank.

The petrol stations I normally use nowadays are all level, so that's not part of it.  When I regularly travelled down the M1 from Luton to London, I often filled at a Gulf station that had a steeply sloping forecourt, so that the fuel cap was highest and the opposite front corner lowest, by quite an angle.  I could get almost 2 extra gallons in at this station, and often saw 200 miles on the trip meter before the first bar of the fuel gauge disappeared!  (These were Gen 1 & 2 Prius with 10 bars on the fuel gauge).  The average error on these were also around 5%, with some higher, some lower.

I've often seen the "EV" light on at up to 60 mph indicated (about 56 true) on my Gen 4 Prius, never higher (Gen 1 & 2 only went to 42 mph on the [inaccurate] speedo, Gen 3 45 mph).

[nellsey]

TBH, if I am averaging anything over 60mpg then I am very happy.

[barrycoll]

When the post-fill-up mileage is suggested as 711 miles, then just 60 mpg wont cut the mustard, dear Nellsey.

If Toyota UK advertised the on-the-road owners mpg, instead of a hypothetical pie in the sky figure, then the advertising would be a lot more convincing for prospective buyers.

So...to help dear Mr T you will have to improve on that bare 60mpg Nellsey, meaning 40 psi tire pressure, and wing mirrors folded in!

 

[PeteB]

5 hours ago, barrycoll said:

When the post-fill-up mileage is suggested as 711 miles...

If Toyota UK advertised the on-the-road owners mpg, instead of a hypothetical pie in the sky figure, then the advertising would be a lot more convincing...

Did you see my post about the mileage estimate being hugely optimistic for the first 4 or 5 fills?  It's much more realistic these days.

[When I got the car with my 'free' full tank, the estimated range was about 860 miles!]

I think manufacturers are only legally permitted to quote the government test results.

[Heidfirst]

18 hours ago, barrycoll said:

If Toyota UK advertised the on-the-road owners mpg, instead of a hypothetical pie in the sky figure, then the advertising would be a lot more convincing for prospective buyers.

 

As Pete says, legally they are only allowed to quote the NEDC test results (at least until the next driving cycle test replaces it shortly). Whilst these are typically 25% or more out these days compared to "real life" hybrids & PHEVs often fair worse.

[barrycoll]

Toyota UK themselves, don't have to quote anything other than NEDC figures.

They only have to state that "Gen 4Prius private owners have found that in the real life driving , xxx mpg have been enjoyed"

 They could be ahead of the legal requirement curve, for on -the-road readings, and so have a lot more credibility

 

[Heidfirst]

Do you really think that they are going to suggest that their cars are 25% less efficient than their competitors just quoting NEDC figures? The whole point of NEDC was to give a common reference point (even if that reference point hasn't translated well into real life comparison).

& it is possible to achieve or even exceed NEDC figures even though most won't.

[barrycoll]

The motoring public now seem faux-surprised that their cars wildly miss NEDC targets .....

The motoring press are now "appalled" that emissions are greater than lab tests suggested.

Change is soon coming to the world of wildly optimistic pie-in-the-sky advertising, and Mr T could earn a few brownie points by one of the first to be up-front honest

[Heidfirst]

It's more a case that people don't understand what the NEDC is. Their cars will hit the NEDC figures under NEDC conditions but NEDC conditions are not average real world conditions.

As I said, there is already a new Driving Cycle Test coming. Will that be perfect? No, but it will be closer to average under real world conditions.

[YarisHybrid2016]

I have a Yaris Hybrid, and it's "official" figure was "85 MPG". Of course, I don't ever think I could achieve that (air resistance), but I have achieved ~76 MPG (real) on a 30 mile trip travelling at 30-55 MPH. My long-term average is around 60 MPG.

I can't speak for the Prius, but the Yaris CC does seem to increase fuel burn, simply due to being very aggressive at maintaining speed (I use less power and let the speed vary).

[PeteB]

1 hour ago, YarisHybrid2016 said:

...I have achieved ~76 MPG (real)...

When you say "real", do you mean on the trip computer display?

I keep tank to tank figures for all four generations of Prius I have driven, and their displayed mpg always seems around 5% optimistic on average.

[YarisHybrid2016]

47 minutes ago, PeteB said:

When you say "real", do you mean on the trip computer display?

I keep tank to tank figures for all four generations of Prius I have driven, and their displayed mpg always seems around 5% optimistic on average.

No, that's why I wrote real. :) :P Computer reported 79.9! :D  I too find it about 5% optimistic (trivia: seems to fit with how much the speedometer over-reads).

[johalareewi]

17 hours ago, YarisHybrid2016 said:

 (trivia: seems to fit with how much the speedometer over-reads).

More trivia:  On the prius trip meter, the mpg figures are higher than actual but the average speed figure is spot on.  Does Yaris trip meter have average speed?

[PeteB]

If you access the internal computers in the Prius or other Hybrids either with a dongle or hand held terminal (or on some versions using a 'hidden' page on the central MFD) the car knows the true speed very accurately, it just fudges it for the speedo in some countries (like all of EU).  US and, I think, Australia, to name but two, get their speedo reporting the accurate speed without the fudge factor.

If you set the speed warning on the built in SatNav you'll find it uses the correct speed too (although you can set a margin for it to activate).

Also, the "Glass of Water" 'game' on some models' central MFD also uses the true speed.

[YarisHybrid2016]

Hi,

Yes - there is an average speed on the MFD and instrument cluster, but I never actually compared them to see what they read! I think they read the same as each other (same data source).

Does it reset the average speed when you reset the average MPG? I never looked! I know it resets when you clear the history.

Hmm - going to go experiment! Would be interesting to see if if average speed can be reset separately.

[johalareewi]

On the gen3 prius, the trip A and trip B meters have mpg and av speed as well as miles. They all reset to zero.

I found a straight flatish empty bit of motorway. Held the speedo at 70mph, reset the trip B meter and kept the speedo at 70mph.

The av speed read 64-65mph same as the gps on the satnav.