4 hours ago, Spock66 said:

To get an accurate reading you need to brim the tank, drive till its nearly empty, refill to the brim and then calculate the fuel consumption.

Trip computers are often not that accurate.

Just filled up a full tank of 57 litres and reset the trip computer. 

4 hours ago, rich1068 said:

If you recall, he had the servicing done using genuine parts including the plugs. He's also on new Bridgestones I believe.

Thanks for the reminder Rich, sorry if I missed something. It’s just that there seems to be a habit of long drawn out conversations attaching to certain posters who shall, and choose to, remain nameless and clearly I’ve not being paying full attention. Mea culpa 🙄.

What I have noticed over a good many years now, no matter what I owned at the time as soon as I filled with premium fuel I noticed the difference.

Still do today in my RX450h, fill with E5 at Tesco (check reviews online) I get better MPG, well I do but even if it is the same I have no doubt that the engine appreciates my choice (as an ex engineer/ mechanic)

 

When running in hybrid mode (not full EV) I routinely get 39mpg around town dropping to 37-38mpg on a high speed (70mph) 200 mile motorway run.

Quite amazing given the size of the car - of course this is with a 4 cylinder 2.5L engine so not quite apples to apples comparison.

I also use E5 as it gives more mpg and is less likely to cause long term problems.

I only use my car for long runs, and it takes about £75 for 300 miles, whatever that works out at. I just pay it, as it is much cheaper to run an old car (no depreciation, purchase cost long ago paid for 2011, low insurance £230 per year). Yes the road tax and petrol and repairs do cost more compared with newer cars, but this is insignificant compared with purchase and depreciation costs.

17 hours ago, b4u2 said:

I've just filled up 57 lites and pressed the reset button, so will see how it goes. I surely do hope to get more out of my tank. 

Now don't press the MPG reset on the display again until you've got a few tanks and a good mix of driving under your belt. 

And you haven't given any detail about driving style or what your regular use is. With reference to @ColinBarber's Fuelly table I'd say our RX and GS are around 80-90% city driving.

Length of journey is a big factor. If you are driving lots of sub 5 mile journeys, with wait time in-between for the engine to cool, your mpg will be significantly worse than other people with a higher trip distance average.

On my  previous GS450h I also saw low MPG but.... I live at the bottom of a hill and every road out of my village is uphill so my hybrid battery was always well charged when I arrived home. I invariably was on ICE when next used due to batteries not being up to optimal temperature. the only non uphill way out of my village from where I live is to walk alongside a stream😂 I have to accept the poor MPG which has improved since changing to a GS300h.

If you drive the car hard and are doing journeys of less than 5 miles, your consumption will be well below average.

For a 3.0 litre RX300, the urban cycle gives 16.1 mpg. I can't remember the RX400h figure.

Short runs from cold really kill mpg. If you get 30 mpg on a run then that is acceptable. As you have had the car fully serviced and the plugs changed then it must be down to the type of journeys you do along with your driving style. 

My only other thought was: "Did they change ALL the plugs?" I understand the rear ones are a PITA to change. Just a thought.

2 hours ago, Spacewagon52 said:

If you drive the car hard and are doing journeys of less than 5 miles, your consumption will be well below average.

For a 3.0 litre RX300, the urban cycle gives 16.1 mpg. I can't remember the RX400h figure.

Short runs from cold really kill mpg. If you get 30 mpg on a run then that is acceptable. As you have had the car fully serviced and the plugs changed then it must be down to the type of journeys you do along with your driving style. 

My only other thought was: "Did they change ALL the plugs?" I understand the rear ones are a PITA to change. Just a thought.

Yes Lexus Guildford confirmed with me that they changed all of the spark plugs. 

Since refuelling and resetting this is what I'm seeing now. 

Hopefully it will go up or if not that, then at least stay not drop.

1 hour ago, b4u2 said:

Since refuelling and resetting this is what I'm seeing now. 

Hopefully it will go up or if not that, then at least stay not drop.

That looks about right

13 hours ago, hughseh said:

That looks about right

It seems to be constantly changing, going up and down all the time.

Does that make sense?

36 minutes ago, b4u2 said:

It seems to be constantly changing, going up and down all the time.

Does that make sense?

Lol, very much so.

As others say, don't reset again. The more miles you do from now on, the more it will iron out any aberrations and settle into a medium term figure. 

 

Mine is 32.0 mpg and a summer of driving around 2,000 miles, mixed types. It will drop closer to 30.0 through the winter 

Just now, hughseh said:

Lol, very much so.

As others say, don't reset again. The more miles you do from now on, the more it will iron out any aberrations and settle into a medium term figure. 

 

Mine is 32.0 mpg and a summer of driving around 2,000 miles, mixed types. It will drop closer to 30.0 through the winter 

Ok thanks Phil.

1 hour ago, b4u2 said:

It seems to be constantly changing, going up and down all the time.

Does that make sense?

Yes.

Don't drive yourself crazy by looking at it after every journey.

I set mine to show average mpg after filling up. I then only check it at next fill up, and ocassionally have a look at the overall average since I've owned the car, which has stayed pretty constant at around 32mpg, despite any daily/weekly/monthly fluctuations.

Eventually you'll get an idea of what fuel and driving style gives you the best mpg.

I drove to Bristol this week, where I spent one night before driving to North Wales where I made a couple of short journeys before returning to Bristol for a night and then back to Devon yesterday, so  fair runs.  I was unusually heavily loaded and averaged overall 32.6mpg.  This included some quite steep hills in Devon and Wales and driving up to the speed limits and without committing myself maybe a little over at times.  I drove it very nearly as hard as I would drive my 5 series BMW. I don't see the point in driving in a very different way to get an additional couple or so mpg.  Whilst in Wales, I met up with my daughter who was driving her Fiesta and joined her for one journey.  What a cramped, noisy and uncomfortable ride that was.  The journeys in the Lexus were well worth the cost of the extra petrol! 

We are blessed to be able to have our Lexii ……. and not be worried for our running costs ……. and mpg 

Malc 

3 hours ago, Malc1 said:

We are blessed to be able to have our Lexii ……. and not be worried for our running costs ……. and mpg 

Malc 

Absolutely! 🙂

Just filled up, so had a look at the consumption, £55 worth of fuel at £1.35 a litre - 9.1 gallons at £6 a gallon, 300 miles, so 32 to the gallon (Wouldn't it be easier if we bought fuel in gallons !). That's motorway running, 5 adults, a dog and a small trailer.

 

3 minutes ago, Russell Wheeler said:

32 to the gallon (Wouldn't it be easier if we bought fuel in gallons !)

Far better for all manufacturers to list Miles per Litre.  Then we could easily compare different cars.

1 hour ago, stepheneric said:

Far better for all manufacturers to list Miles per Litre.  Then we could easily compare different cars.

How about miles per kWh?

2 hours ago, stepheneric said:

Far better for all manufacturers to list Miles per Litre.

Mixing metric and imperial does not make much sense (just like tyre sizes).

The phenomenon was developed to create confusion ……. quite successfully I’m sure ! 
Malc 

2 hours ago, Spock66 said:

5 hours ago, stepheneric said:

Far better for all manufacturers to list Miles per Litre.

Mixing metric and imperial does not make much sense (just like tyre sizes).

Totally agree

In UK we already have a mixture of Metric (litres - cannot buy gallons) and Imperial (roads in miles). We have to live with it so, Manufacturers

can make life a lot simpler by quoting miles per litre which I find a lot easier to than the european system of litres per 100 kilometres - takes the back of a few fag packets to work out

as shown in Russel's original comment.