Poor MPG in 2013 F sport

[wharfhouse]

1 minute ago, agent_dess said:

It was 12degrees on Sunday. And Sunday was an unsual day in which I made two 30miles round trip that day. My normal day is 5-6miles around town.  I think if I did longer trips daily I would start to exceed 35mpg.  My tyres are recommended pressure for 18".  I'm so ecstatic with 35mpg 🤣

Yes short trips in cold weather doesn't let the hybrid deliver much benefit over an ICE - longer trips and/or warmer weather make a big difference allowing the hybrid tech to work much more effectively. My overall average mpg over 60k miles in 5 years and with a good mix of long and short journeys is around 48mpg (on the car computer). 

[NemesisUK]

9 minutes ago, wharfhouse said:

Yes short trips in cold weather doesn't let the hybrid deliver much benefit over an ICE

Now, I would say the opposite! Hybrids warm so much more quickly, they get help from the Battery during the warm-up. My only experience is with the RC300h, a massive improvement over the ICE cars I've had before but I must say the 2nd generation RC is even better than it's predecessor. Lexus have tweaked something so it delivers consistent mpg no matter the length of the journey.  

[agent_dess]

I remember the days when my 1.0L yaris used to give me 50-55mpg😁

[agent_dess]

I'm wondering apart from the shoddy tyre I currently have, if the hybrid Battery is is slowly dying resulting in the petrol engine picking up more of the slack in performance resulting in poorer mpg.

[NemesisUK]

Have you had a hybrid health check done on the car?

[agent_dess]

5 minutes ago, NemesisUK said:

Have you had a hybrid health check done on the car?

Yeah that was done along with 70k service back in January hybrid health check was a pass I've also changed the spark plug back in February. Cleaned the hybrid fan and filter and keep all tyres at 36. I do my best to accelerate slowly, brake early and use control as much as possible.

[wharfhouse]

56 minutes ago, NemesisUK said:

Now, I would say the opposite! Hybrids warm so much more quickly, they get help from the battery during the warm-up. My only experience is with the RC300h, a massive improvement over the ICE cars I've had before but I must say the 2nd generation RC is even better than it's predecessor. Lexus have tweaked something so it delivers consistent mpg no matter the length of the journey.  

Yes you're right - after all the miles in my  IS 300h I forget how bad the mpg was on my ICE cars on short journeys when cold! However short journeys from a cold start in cold weather do still negatively hit the hybrid mpg but it is still performing better than an equivalent ICE only car. 

[agent_dess]

In the IS250 I used to get 20-27mpg round town 30-35mpg on long runs and even 40-42mpg on trips to London. 

Lexus quote 60 odd mpg for the IS300h surely I should be able to get 40-45mpg without having to drive like a snail 

🐌

In short I'm not really any better off than I was in is250.

[wharfhouse]

3 hours ago, agent_dess said:

In the IS250 I used to get 20-27mpg round town 30-35mpg on long runs and even 40-42mpg on trips to London. 

Lexus quote 60 odd mpg for the IS300h surely I should be able to get 40-45mpg without having to drive like a snail 

🐌

In short I'm not really any better off than I was in is250.

Like I said you should be able to get better mpg than you are seeing and certainly on like for like journeys compared to your IS 250. The old figures that car makers quoted for mpg were never achievable in real world driving but the new WLTP figures are and for The IS 300h Lexus quoted around 48mpg which is what I have been achieving. Something does seem amiss with what you are seeing. 

[wharfhouse]

9 hours ago, wharfhouse said:

Like I said you should be able to get better mpg than you are seeing and certainly on like for like journeys compared to your IS 250. The old figures that car makers quoted for mpg were never achievable in real world driving but the new WLTP figures are and for The IS 300h Lexus quoted around 48mpg which is what I have been achieving. Something does seem amiss with what you are seeing. 

You may well have checked all these things but if not maybe worth a look at:

- brakes - are any wheels getting unusually warm - if so could be a sticking brake caliper

- wheel alignment - is the car running true and straight as any issues may be scrubbing tyres losing efficiency 

- tyres - some tyres (as I think you have mentioned) are not so good for economy - and make sure you check tyre pressures with a good quality tyre pressure gauge when cold (not at a fuel station as they are invariably inaccurate) - under inflation seems to have a significant effect on mpg - if anything go a touch over (I go to 3.6 bar instead of the quoted 3.5 bar)

- oil - was the car last serviced by Lexus or a 3rd party - if the latter and heavier oil than spec was used this can increase fuel consumption 

- air filter - worth a look as it's not always replaced at a service and see if it's particular dirty 

- 12V Battery - have you had any issues there leaving it for a few days - if the 12V Battery is weak the traction Battery will be constantly recharging it leaving less power from the traction Battery to help economy via the hybrid sysyem

- you said the last hybrid healthcheck was all clear and plugs have been replaced as per schedule

- I saw you posted in the thread about the Battery filter and cleaned that so shouldn't be a problem there 

- there are mixed reports on the E10 fuel impacting mpg - I am still trying to decide what the impact is - sometimes I seem to see better mpg with E10 over what I had previously (though can't explain that) especially after just refueling but then at other times it seems worse like when it's been in the tank a couple of weeks - you could try E5 for a few fills and see what that does

As a benchmark - if the weather is warmish (let's say 15C), the car is unladen (so just you and maybe one passenger max) the road is level, speed is reasonably constant at around 70mph such as on a motorway then you should easily get 45mpg+ (I can get to around 50mpg+ like this) and on A roads at say 50-60mph constant speed you should be seeing 50mpg and maybe more. Around town in similar conditions high 40s mpg is also quite achievable depending on how much stop start and how quick you need to accelerate. 

If you aren't getting these sort of mpg after the above checks then it may be worth also getting a full service done (not sure when your last one was done or who did it) possibly at a Lexus dealer? 

NB: All my mpg is measured on the car computer 

 

[route66]

These are my MPG stats over 65 fills and 4.5 years:

• Minimum: 31.7 MPG
• Maximum: 47.85 MPG
• Average: 40.19 MPG

The above are from my own calculations based on brim-brim checks; the trip computer is on average 7% optimistic (ranges from 5 - 10%). I have also found the range estimate pessimistic - typically I could get 50 miles in addition to what is reported.

Also, in the winter, the consumption is worse and most especially on short trips. You can help this greatly by not switching on the heating (I know ...). When stationary in traffic on cold days, you will find that the engine runs constantly to keep the heat going. Reduce the temp to "Lo" and the engine will cut out. If you have electric seat heaters (and no rear-seat passengers), use these instead!

I have 17" wheels with Bridgestone tyres on the back and Dunlops on the front (don't ask ...)

 

[rayaans]

It's this crap fuel. 

Ive noticed on the C200 it's getting almost 2-3mpg less than it was on E5 in town and up to 5mpg on a good run.

 

[agent_dess]

3 hours ago, rayaans said:

It's this crap fuel. 

Ive noticed on the C200 it's getting almost 2-3mpg less than it was on E5 in town and up to 5mpg on a good run.

 

I've never used E10 I always get Tesco Momentum E5

[wharfhouse]

3 minutes ago, agent_dess said:

I've never used E10 I always get Tesco Momentum E5

Wow that's even more worrying... I would have expected a few percent better fuel consumption from using Super Unleaded over the old E5 and then more still over the new E10 - in my case that would certainly add a few mpg to what I am seeing on E10. Keep thinking of trying Super Unleaded E5 again but as it's around 8% more than E10 at the moment I think it would probably end up costing me even more per mile than E10 as I'm not sure I'll get 8% better mpg from it.

[agent_dess]

I have

1 x Sailwin Sportway 56 tyre fuel rating E.

3 x Joyroads Sports RX6 tyre fuel rating E.

I would never but tyre with Fuel rating less than C worse case scenario.

[agent_dess]

6 minutes ago, wharfhouse said:

Wow that's even more worrying... I would have expected a few percent better fuel consumption from using Super Unleaded over the old E5 and then more still over the new E10 - in my case that would certainly add a few mpg to what I am seeing on E10. Keep thinking of trying Super Unleaded E5 again but as it's around 8% more than E10 at the moment I think it would probably end up costing me even more per mile than E10 as I'm not sure I'll get 8% better mpg from it.

The reason I have stuck to E5 is so many reports of people getint poor economy on E10 + engine light turning on. For me Tesco Momentum is the only E5 option all other pumps are now E10 in my area.

[wharfhouse]

4 minutes ago, agent_dess said:

I have

1 x Sailwin Sportway 56 tyre fuel rating E.

3 x Joyroads Sports RX6 tyre fuel rating E.

I would never but tyre with Fuel rating less than C worse case scenario.

I have Yokohama BluEarth E51A (225/45 R17 ) all round which was the OEM tyre the car came with and I've put the same on each time. Just had a look at their fuel efficiency rating and it's D (never actually looked before what they were) so if you have E rating that shouldn't make much difference. Mind you with the tyres you have on there I'd be getting them changed out quickly for 4x of a reputable brand...

[wharfhouse]

4 minutes ago, agent_dess said:

The reason I have stuck to E5 is so many reports of people gett poor economy on E10 + engine light turning on. For me Tesco Momentum is the only E5 option all other pumps are now E10 in my area.

I have had no issues running with E10 - I fill up probably 90% of the time at my local Sainsburys (and the rest of the time wherever I need to) and the car runs just as smoothly as it did in the past and I haven't noticed any loss in power - and in some circumstances seems to actually give better mpg, though as time has gone on, on balance I do think it's worse overall.

[agent_dess]

Process of elimination 😂 where do I go from here, I was hoping it would be the crap tyres.

[wharfhouse]

6 minutes ago, agent_dess said:

Process of elimination 😂 where do I go from here, I was hoping it would be the crap tyres.

Still could be to some degree as mixed tyres of cheap construction may be a bigger contributor than their rating - only changing them out would confirm though. But I would change them anyway for peace of mind of having a decent set of tyres. If you have been through the list I sent earlier today then other than a good full service not really sure... 

[agent_dess]

9 minutes ago, wharfhouse said:

Still could be to some degree as mixed tyres of cheap construction may be a bigger contributor than their rating - only changing them out would confirm though. But I would change them anyway for peace of mind of having a decent set of tyres. If you have been through the list I sent earlier today then other than a good full service not really sure... 

Yeah I was planning to change them next month as they are scary in the wet when going round the roundabout lol time for wheel spins to burn them out 🤪

[agent_dess]

https://mag.lexus.co.uk/hybrid-driving-lexus-top-tips-for-best-fuel-economy/comment-page-1/

Educational read..

[wharfhouse]

2 minutes ago, agent_dess said:

https://mag.lexus.co.uk/hybrid-driving-lexus-top-tips-for-best-fuel-economy/comment-page-1/

Educational read..

Yes that's a good article - to be fair after a while you do get used to driving hybrids economically but still maintaining good progress. I don't max out the mpg by any means as I'm usually trying to get places to a schedule but I do tend to drive in a way so I don't use fuel needlessly! 

[agent_dess]

I really think the hybrid Battery isn't run at optimum.

Looking at testimonial on Hybrid Battery Solutions:

Massive thank you to Richard at Hybrid Battery Solutions. My GS450H had a check Hybrid message and had lost some ‘oomph’ and mpg. On my drive down to get the Battery conditioned I achieved 26.2mpg average. 

The return journey was 38mpg (and I was in a hurry!). Really pleased – the car feels like it has been remapped and is back to ‘as new’ condition. Highly recommended”

what I have noticed is at night I will park car, hybrid Battery will be nearly full. But some days when I leave the following day Battery is only 1-2 bars.  I think it's not holding capacity and the engine waste fuel charging the Battery.  I will reach out Richard for advice and see what he says.  I discovered my car was a taxi in a previous life which may explain alot.

[wharfhouse]

4 minutes ago, agent_dess said:

I really think the hybrid battery isn't run at optimum.

Looking at testimonial on Hybrid Battery Solutions:

Massive thank you to Richard at Hybrid Battery Solutions. My GS450H had a check Hybrid message and had lost some ‘oomph’ and mpg. On my drive down to get the battery conditioned I achieved 26.2mpg average. 

The return journey was 38mpg (and I was in a hurry!). Really pleased – the car feels like it has been remapped and is back to ‘as new’ condition. Highly recommended”

what I have noticed is at night I will park car, hybrid battery will be nearly full. But some days when I leave the following day battery is only 1-2 bars.  I think it's not holding capacity and the engine waste fuel charging the battery.  I will reach out Richard for advice and see what he says.  I discovered my car was a taxi in a previous life which may explain alot.

It could be an issue as I wouldn't expect the traction Battery to lose that much of its charge being left a few days but can't see I've ever checked mine. I don't see why being a taxi should kill the traction Battery more than any other driving - my car is now on 115k miles and others have done much more than that without Battery issues. However if you can get it checked worth a look. If you have had the Hybrid health check in the past 10k miles / 12 months the Battery can be kept in warranty by doing the hybrid health check every 10k miles / 12 months for up to 15 years of age with no mileage limitation.