Poor MPG on a new is300h

[Ishay]

Hi,

After 185 Miles i'm getting ~30 MPG.

Driving mostly in Normal mode and 60-70% of the time on urban roads.

Is it normal for a new car?

Thanks,

Ishay

 

[Zotto]

It depends  on how heavy is your right foot.

[Ishay]

1 minute ago, Zotto said:

It depends  on how heavy is your right foot.

Not that heavy actually.

Not accelerating that hard except maybe a very few times.

 

[malcolmw]

Right from new our IS300h did about 43mpg (indicated) on mixed driving. It has now done 12K miles and is at about 46mpg overall.

[NemesisUK]

Give it a few tank fulls before comparing. 

Do the brim-to-brim calculations and compare with the OBC figures.

[route66]

Have a look on Fuelly for details on what other IS300H drivers are getting: http://www.fuelly.com/car/lexus/is300h.

Based on Fuelly, 30 MPG would be an off-the-scale terrible average - it looks like 37 MPG is the worst average listed.

My brim-to-brim summary:

• Worst 31.7 MPG
• Best 44.6 MPG
• Average 39.5 (over 18 refuels)

Bear in mind, the number your computer reports will always be optimistic - by about 10%. Your consumption will always be worse when the weather gets cold. Wait for a warm day when your averaging 50 MPH on a B-road and you'll see 60+ MPG reported 😁

[Ishay]

31 minutes ago, malcolmw said:

Right from new our IS300h did about 43mpg (indicated) on mixed driving. It has now done 12K miles and is at about 46mpg overall.

I though it takes time for the car to settle. I must be driving it wrong then.

 

10 minutes ago, route66 said:

Have a look on Fuelly for details on what other IS300H drivers are getting: http://www.fuelly.com/car/lexus/is300h.

Based on Fuelly, 30 MPG would be an off-the-scale terrible average - it looks like 37 MPG is the worst average listed.

My brim-to-brim summary:

• Worst 31.7 MPG
• Best 44.6 MPG
• Average 39.5 (over 18 refuels)

Bear in mind, the number your computer reports will always be optimistic - by about 10%. Your consumption will always be worse when the weather gets cold. Wait for a warm day when your averaging 50 MPH on a B-road and you'll see 60+ MPG reported 😁

Weather here in Israel is not that bad actually, it's around 17 degrees Celsius in it's lowest so no issue there i guess.

I saw that 7 people who own 2015 model reported 32.7 mpg on average on Fuelly.

 

[Zotto]

There could be some confusion due to different mpg conversion ;-). A km/l expectable result is about 16 km/l, but this has to be intended after some thousands of km. done and learning ho to drive hybrid, try to reach relatively fast cruise speed and then keep eco indicator in eco zone just a bit over the center mark.

[Mr Vlad]

Is this your first hybrid? Is this your first auto?

When I got my first is300h I found it awful. My second is300h was superb. Same age/spec/everything except the reg plate.

I remember getting low low 30''s in my 1st but regular 50''s in my 2nd. I had an auto box mondeo between the two lexus cars.

As above. Get to desired speed briskly then keep foot steady so needle stays in eco bit.

[Pink]

Had mine for just over a month and I’m getting about 49. Mainly because almost all my M4 commute (50 mile round trip daily) is currently restricted to 50mph due to Smart motorway roadways, so it’s impossible to be too heavy footed. Because of that I’m in Eco mode for most of the time which is probably helping, and especially in the slow crawling traffic on the way to the motorway when I’ll put it in eco as much as possible, simply cuz I’m only doing 2mph anyway! 

[Thackeray]

54 minutes ago, Zotto said:

There could be some confusion due to different mpg conversion ;-)

This is probably obvious but discussions on this UK website are using UK gallons, which are bigger than US gallons. It might be that in Israel your car is set to show US gallons and US mpg. For example, 30 US mpg is about 36 UK mpg.

You can check by changing to another measure, like km/litre or litres/100km, which I think is used in much of mainland Europe.

So for example, 36 UK mpg (or 30 US mpg) is about 7.8 litres/100km. If you're not sure, it's probably best to check first whether you're on US or UK gallons.

[Ishay]

2 hours ago, Zotto said:

There could be some confusion due to different mpg conversion ;-). A km/l expectable result is about 16 km/l, but this has to be intended after some thousands of km. done and learning ho to drive hybrid, try to reach relatively fast cruise speed and then keep eco indicator in eco zone just a bit over the center mark.

I'm getting ~13.5km/l which is still relatively high consumption. 

 

2 hours ago, Mr Vlad said:

Is this your first hybrid? Is this your first auto?

When I got my first is300h I found it awful. My second is300h was superb. Same age/spec/everything except the reg plate.

I remember getting low low 30''s in my 1st but regular 50''s in my 2nd. I had an auto box mondeo between the two lexus cars.

As above. Get to desired speed briskly then keep foot steady so needle stays in eco bit.

It is my first hybrid. So you are saying that they have bad QA in Lexus or that you've learnt how to drive hybrid cars on your second one?

 

1 hour ago, Thackeray said:

This is probably obvious but discussions on this UK website are using UK gallons, which are bigger than US gallons. It might be that in Israel your car is set to show US gallons and US mpg. For example, 30 US mpg is about 36 UK mpg.

You can check by changing to another measure, like km/litre or litres/100km, which I think is used in much of mainland Europe.

So for example, 36 UK mpg (or 30 US mpg) is about 7.8 litres/100km. If you're not sure, it's probably best to check first whether you're on US or UK gallons.

It is obvious except that I didn't know there's a difference between UK galon and US galon(Thank you for that!)

Based on the new information, my consumption is 36 mpg which is still on the higher side but much better then 30 lol.

 

[zippyone]

Hi Ishay,

good to see you again. I use `Fuelly,` and also a German site, ` Spiritmonitor.de.` My 2013 300h gave me 5.3 l/100 km ~ 53.5 mpg imp, ~ 44.39 US. on 17 inch shoes.

My 2018 300h is giving me 6.0 l/100 km ~ 47.09 mpg imp, ~ 39.27 US.. The 2018 model is a tad heavier and wears 18 inch shoes.

I fill to the brim each time. Bad economy to me is if i get less than 1020 km from a tank of fuel.

A little trick to assist economy, wear house slippers, the soles being thinner give a better sense of  touch, between your plantar and the pedal. You will soon perfect the amount of movement required in your ankle to get the beast mobile. only a small amount of pressure is required, you`ll work it out easily.

I live in metric land and use phone apps to change distance/volume to imperial/us. too bloody old at 72 to do it in my cranium. ha ha.

Good luck enjoy your ride,

Best wishes.

Michael.

 

[Ishay]

56 minutes ago, zippyone said:

Hi Ishay,

good to see you again. I use `Fuelly,` and also a German site, ` Spiritmonitor.de.` My 2013 300h gave me 5.3 l/100 km ~ 53.5 mpg imp, ~ 44.39 US. on 17 inch shoes.

My 2018 300h is giving me 6.0 l/100 km ~ 47.09 mpg imp, ~ 39.27 US.. The 2018 model is a tad heavier and wears 18 inch shoes.

I fill to the brim each time. Bad economy to me is if i get less than 1020 km from a tank of fuel.

A little trick to assist economy, wear house slippers, the soles being thinner give a better sense of  touch, between your plantar and the pedal. You will soon perfect the amount of movement required in your ankle to get the beast mobile. only a small amount of pressure is required, you`ll work it out easily.

I live in metric land and use phone apps to change distance/volume to imperial/us. too bloody old at 72 to do it in my cranium. ha ha.

Good luck enjoy your ride,

Best wishes.

Michael.

 

Hi Michael!

You are getting some good numbers!

I usually drive bare footed so my sensitivity is at max and my Lexus has 17 inch wheels.

1000+ km from one tank is great! let’s see how many km I can squeeze out of one tank. At the moment I have 3/4 tank left and already drove 300 km. 

[Thackeray]

4 hours ago, Ishay said:

I'm getting ~13.5km/l which is still relatively high consumption. 

..........

Based on the new information, my consumption is 36 mpg which is still on the higher side but much better then 30 lol.

 

This is getting a bit confusing! 13.5 km/litre is around 21 mpg (imperial - ie UK) which doesn't look right, and is a lot different from 36 mpg.

Which makes me wonder if there are some other issues here? Namely, where are you getting the figures from? Are they your own calculations based on full tanks of fuel bought? I suspect not if you've only done 185 miles in a brand new car.

So are you reading the numbers from the dashboard? If so, there are different options you could be seeing. Does the dashboard say "After Reset", meaning since you pressed a button to reset the start time for the consumption figure? Or does it say "After Refuel", giving the mpg since you filled up the tank? Or does it say "After Start", meaning for the current trip since you turned the car on? 

If you're using the "After Start" setting, you're probably seeing inconsistent figures as each trip is measured separately and starting with a cold engine is always going to increase fuel consumption (lower mpg). It's probably best to look at the "After Reset" figure to get a more realistic long-term figure. Though calculating from tanks of fuel bought will be more accurate.

[steveledzep]

I just did a very quick mental calculation and 13.5km/litre equates roughly to 38mpg.

[Thackeray]

2 minutes ago, steveledzep said:

I just did a very quick mental calculation and 13.5km/litre equates roughly to 38mpg.

Whoops! Absolutely correct. Serves me right for using a conversion website rather than thinking.

[Undziak]

I achieve without any problems 5,2 - 5,5 l/100km (according to BC). Real consumption is BC + 0,6l. There was one tour, I drove slowly (100-120 km/h) and achieved 4,6l on BC, range almost 1200 km. Worst consumpution I had - 8,2 on BC (real 8,2 + 0,6=8,8 l) - in Germany 180-200 km/h.

[Ishay]

2 hours ago, Thackeray said:

This is getting a bit confusing! 13.5 km/litre is around 21 mpg (imperial - ie UK) which doesn't look right, and is a lot different from 36 mpg.

Which makes me wonder if there are some other issues here? Namely, where are you getting the figures from? Are they your own calculations based on full tanks of fuel bought? I suspect not if you've only done 185 miles in a brand new car.

So are you reading the numbers from the dashboard? If so, there are different options you could be seeing. Does the dashboard say "After Reset", meaning since you pressed a button to reset the start time for the consumption figure? Or does it say "After Refuel", giving the mpg since you filled up the tank? Or does it say "After Start", meaning for the current trip since you turned the car on? 

If you're using the "After Start" setting, you're probably seeing inconsistent figures as each trip is measured separately and starting with a cold engine is always going to increase fuel consumption (lower mpg). It's probably best to look at the "After Reset" figure to get a more realistic long-term figure. Though calculating from tanks of fuel bought will be more accurate.

Reading from the dashboard and After reset. I’ll to reset it and try again.

 

 

[Carter]

I own an IS 300h 2013 model for exactly 6 months now and my average is now 5.87 l/100km (or 17.0 km/l). I'll stick to the metric numbers since I know there US and UK gallon which need to be taken into account when converting into MPG.

I have to admit that in the first 2-3 months I was only getting 6.2 l/100km (16.1 km/l) on average, even though that was the summer period. I'm currently on summer tyres as well (will not be changing for maybe a week of snow here in The Netherlands) and my last refuelling came in at 5.84 l/100km while it was constantly between 0 and 8 C outside. I measures using the Spritmonitor app, so this is the actual mileage, the dashboard info seems to be off by at least 0.5 l/100km (it shows 5.3 l/100km when it actually is 5.8 for example).

Note that I said during the first 2-3 months I had a worse mileage, I come from a Lexus CT 200h 2012 (drove it for a year until I had to replace it) and a Prius II 2006 before that. What I notice is the different driving style approach you need to have with the heavier IS compared to the CT or Prius, which are almost equal. Both the CT and Prius you could drive calmly and get about 4.5-5 l/100km (20-22 km/l) or absolutely trash it and drive 180 km/h on the Autobahn and still get at least 5.5 l/100km (18 km/l) at worst, even in the winter. I bet this is largely due to their ICE of only 100 hp compared to the 181 hp of the IS. I also notice that while the IS has a much stronger electric motor that is being used even at 120 kph and therefore contributes to being able to run those high speeds and still only 1300 rpm or something. However, my strategy when I wanted to drive calmly and save some fuel in the CT or Prius doesn't work in the IS at all! In the CT/Prius I would use Eco mode and only put my foot down until the eco meter was exactly where the power area started. When I do that with the IS, it seems to use the ICE a lot and keep it between 2000-3000 rpm, but since it takes so long (relatively) to reach the necessary speed, it seems to use a lot more fuel. I spoke about this with the Lexus dealer and they advised me to reach the given speed as quickly as possible, but not so quick that you're giving full throttle, I tend to keep the needle of the eco meter about halfway in the power area. After I reach 50/80/100/120 kph I can let go and the ICE immediately goes down in rpm.

This has made it more efficient in the last 3-4 months compared to the beginning. And while it's not a huge amount more efficient, it's enough to drive like this, especially since it's actually faster and less annoying to those Audi's behind you. ;-) I know I could gain more by braking more slowly (more regen and saving the actual brakes as an added bonus) and I've recently started using the EV mode as much as possible as advised by some Lexus dealer video on YouTube. During my normal commute I know when I get home, take the exit on the highway and enter the neighbourhood there's a little less than 2 km to go on 30 and 50 roads (kph). I now do that completely using the EV mode, even at 2 C outside it's not an issue. In the morning that means the Battery is almost empty, but since the whole system needs to warm up anyway, most of the lost energy from heating up goes to the Battery pack and when I arrive at the highway again, the Battery is full enough (2/3) to quickly enter it without having to rely on the ICE alone.

[wharfhouse]

47 minutes ago, Carter said:

I own an IS 300h 2013 model for exactly 6 months now and my average is now 5.87 l/100km (or 17.0 km/l). I'll stick to the metric numbers since I know there US and UK gallon which need to be taken into account when converting into MPG.

I have to admit that in the first 2-3 months I was only getting 6.2 l/100km (16.1 km/l) on average, even though that was the summer period. I'm currently on summer tyres as well (will not be changing for maybe a week of snow here in The Netherlands) and my last refuelling came in at 5.84 l/100km while it was constantly between 0 and 8 C outside. I measures using the Spritmonitor app, so this is the actual mileage, the dashboard info seems to be off by at least 0.5 l/100km (it shows 5.3 l/100km when it actually is 5.8 for example).

Note that I said during the first 2-3 months I had a worse mileage, I come from a Lexus CT 200h 2012 (drove it for a year until I had to replace it) and a Prius II 2006 before that. What I notice is the different driving style approach you need to have with the heavier IS compared to the CT or Prius, which are almost equal. Both the CT and Prius you could drive calmly and get about 4.5-5 l/100km (20-22 km/l) or absolutely trash it and drive 180 km/h on the Autobahn and still get at least 5.5 l/100km (18 km/l) at worst, even in the winter. I bet this is largely due to their ICE of only 100 hp compared to the 181 hp of the IS. I also notice that while the IS has a much stronger electric motor that is being used even at 120 kph and therefore contributes to being able to run those high speeds and still only 1300 rpm or something. However, my strategy when I wanted to drive calmly and save some fuel in the CT or Prius doesn't work in the IS at all! In the CT/Prius I would use Eco mode and only put my foot down until the eco meter was exactly where the power area started. When I do that with the IS, it seems to use the ICE a lot and keep it between 2000-3000 rpm, but since it takes so long (relatively) to reach the necessary speed, it seems to use a lot more fuel. I spoke about this with the Lexus dealer and they advised me to reach the given speed as quickly as possible, but not so quick that you're giving full throttle, I tend to keep the needle of the eco meter about halfway in the power area. After I reach 50/80/100/120 kph I can let go and the ICE immediately goes down in rpm.

This has made it more efficient in the last 3-4 months compared to the beginning. And while it's not a huge amount more efficient, it's enough to drive like this, especially since it's actually faster and less annoying to those Audi's behind you. ;-) I know I could gain more by braking more slowly (more regen and saving the actual brakes as an added bonus) and I've recently started using the EV mode as much as possible as advised by some Lexus dealer video on YouTube. During my normal commute I know when I get home, take the exit on the highway and enter the neighbourhood there's a little less than 2 km to go on 30 and 50 roads (kph). I now do that completely using the EV mode, even at 2 C outside it's not an issue. In the morning that means the battery is almost empty, but since the whole system needs to warm up anyway, most of the lost energy from heating up goes to the battery pack and when I arrive at the highway again, the battery is full enough (2/3) to quickly enter it without having to rely on the ICE alone.

Personally I don't think it's worth pressing the EV mode unless I am just moving the car a few metres on the driveway or when I first start it up and sat stationary for a while (like sorting out the sat nav or something). You are right with the advice given about accelerate reasonably quickly and smoothly to the desired speed - if you then lift off the accelerator completely for a split second and you under about 45mph with a decent amount of Battery (at least in ECO mode anyway) the car will go into EV mode on it's own straight away - if you use ** very ** light throttle / coasting to maintain a constant speed when driving below 45mph the car can go a surprisingly long way on EV with only very limited time running the engine if you need to accelerate back up to speed again. It's quite common to see 50 - 60+ miles per gallon (UK gallons) in these circumstances. Cold weather definitely reduces efficiency - partly due to the engine running to maintain heat and heat the car and partly due I assume to batteries not working so well when it's cold until they warm up.

[olliesgrandad]

On my third Lexus hybrid and rarely use eV mode or eco mode. I get a genuine tank to tank range of between 30 and 34mpg. When I had an IS300h f sport I got 45mpg all day long. Watch the Lexus YouTube video on driving a hybrid. Some useful tips there. 

[Hadrian]

We dont use our is300 for any short  trips, so it's nearly all dual carriageways and "A" roads.

I haven't done a tank to tank check, but going by the computer display we are getting a steady 50.5 mpg.

[DanD]

@Ishay Do you live in a hilly area? - This would have an impact on your fuel consumption...

[Richard1200]

Retired, only short journeys, no Motorway and I get the high 47’s. 16;200 miles since May 2015.

Only reset the average once in over 3 years and that was 10 months ago when I had 12v Battery issues.

Since February it had been 47.5 to 48 (for a short time) The last 10 days since the cold weather it has gone from 47.7 to 47.0

All in ECO mode as I find this softer and smoother than Normal. I have tried Sport a few times but it’s too much for me, maybe 30 years ago, but not now.