RX450h MPG Computer vs Actual

[steveledzep]

Had my RX since beginning of March and I've recorded mileage and fill-ups on a spreadsheet.  Just got back today from a trip to Scotland and back.  From Carmarthenshire to Chester, to Blackpool, to Kendal. to Glasgow, to Stirling, to Edinburgh, to Ashington, to York, to Leamington Spa and then home earlier today.

 

The below spreadsheet shows my actual mpg calculations and the photograph shows the computer mpg up to my trip and then during my trip.

 

I read a lot on here about the computer over-stating the mpg......doesn't seem to be the case on my vehicle .  Thought you guys might like to know.

 

DATE	LITRES	LOCATION	JOURNEY	MILEAGE	MILES/TANK	MODE	MPG TANK	COST	PPM TANK
04/03/17	Fill	Gorslas		55,542	-		-
22/03/17	44.46	Gorslas	Local	55,840	298	Normal	30.47	£52.42	£0.18
11/04/17	41.83	Gorslas	Local	56,116	276	Normal	30.00	£49.73	£0.18
02/05/17	40.38	Gorslas	Local	56,380	264	Normal	29.72	£48.02	£0.18
23/05/17	43.96	Gorslas	Local	56,684	304	Normal	31.44	£51.38	£0.17
08/06/17	51.51	Gorslas	Local	57,057	373	Normal	32.92	£60.21	£0.16
15/06/17	49.21	Penrith	Home, Chester, Blackpool, Kendal	57,449	392	Normal	36.21	£57.53	£0.15
18/06/17	48.33	Seaham	Glasgow, Stirling, Edinburgh, Ashington	57,826	377	Normal	35.46	£58.58	£0.16
20/06/17	50.51	Gorslas	York, Leamington Spa, Home	58,248	422	Normal	37.98	£58.54	£0.14

[malcolmw]

Here's my record since I got my new type RX last September.

Date	Mileage	Fuel Gal	MPG	MPG Car
02/09/16	10
16/09/16	362	10.41	33.83	33.50
09/10/16	732	11.21	33.00	32.90
26/10/16	1108	11.00	34.17
09/11/16	1467	10.91	32.91	32.60
02/12/16	1807	10.99	30.93	30.40
16/12/16	2060	7.94	31.88	31.50
23/12/16	2420	10.40	34.63	34.00
06/01/17	2746	10.26	31.78	32.30
23/01/17	3109	11.33	32.03	30.50
11/02/17	3485	12.78	29.41	29.40
25/02/17	3901	12.12	34.33	33.20
15/03/17	4267	11.27	32.48	31.80
05/04/17	4643	11.24	33.45	32.90
01/05/17	4965	10.24	31.45	31.80
17/05/17	5339	10.97	34.10	34.10

 

The last 2 columns are the actual calculated MPG from the fuel put in and the readout from the "mpg since last fuel".

The on-board metering seems pretty accurate to me also. 

[steveledzep]

Interesting that you're experiencing accurate computer mpg too Malcolm.

I didn't actually check, but I always felt my previous two ISs overstated the mpg.