New owner questions!

[Stever750]

On 3/16/2024 at 4:01 PM, ColinBarber said:

Trip computer can be up to 3 mpg out in my experience. 

Filled up again yesterday, similar value on the trip at 46.0mpg, actual was 43.3 this time, so not so far away. Thus far I can deduce there is a measurement bias with a large degree of uncertainty. 

[Notamech]

2 hours ago, Stever750 said:

Filled up again yesterday, similar value on the trip at 46.0mpg, actual was 43.3 this time, so not so far away. Thus far I can deduce there is a measurement bias with a large degree of uncertainty. 

Is this with the climate control on? If so once summer rolls around and if it isnt too hot outside you can get away with just using the fan and your mpg will go up even further. The highest i seen in the summer was 53 with climate control off cruising at 60-65mph on a motorway. This was just on the display though like you say could be off by a bit. Also depending on how old your car is you might want to get the Battery fan and filter cleant. Anecdotally it helps stretch your mpg a mile or so more.

[Stever750]

12 minutes ago, Notamech said:

Is this with the climate control on? If so once summer rolls around and if it isnt too hot outside you can get away with just using the fan and your mpg will go up even further. The highest i seen in the summer was 53 with climate control off cruising at 60-65mph on a motorway. Also depending on how old your car is you might want to get the battery fan and filter cleant. Anecdotally it helps stretch your mpg a mile or so more.

CC always off be default for that reason. Car is a used Lexus "Select" and has just been serviced, so I am making an assumption that the fan and filter are working as they should be.

[Notamech]

6 minutes ago, Stever750 said:

CC always off be default for that reason. Car is a used Lexus "Select" and has just been serviced, so I am making an assumption that the fan and filter are working as they should be.

Unfortunately the fan and filter cleaning is not a something on any service schedule as far as I am aware. Depending on the age of the car and how much use the rear seats get the filter tends to accumulate quite a bit of crud that reduces air flow. While it still works its not at its best and hence Battery usage reduces. You wont get any error on the display until its severely blocked and thats the only time lexus will clean it. 

I did mine at ~90k miles/8 years old and was surprised at the crap that came out. If your car is relatively new / low miles its probably working optimally already. Heres a thread on it in case you fancy having a read or plan to do it yourself. 

 

[Stever750]

Another refuel, trip said 42.3, app calculated 39.5 What's slightly bizarre is that the average dropped by around 3mpg after a 220 mile on the M4, followed by pootling around the lanes of Pembrokeshire for the last couple of weeks. Could that be a symptom of impaired Battery cooling? using E5 petrol makes no difference either.

Other things I've tried an wondered just how/why is the manual sport mode with the paddles. Briefly tried it, and thought it might just be an engine revs thing; but how is it supposed to work? And just why on a vehicle with a CVT

[TheMcSame]

2 hours ago, Stever750 said:

Another refuel, trip said 42.3, app calculated 39.5 What's slightly bizarre is that the average dropped by around 3mpg after a 220 mile on the M4, followed by pootling around the lanes of Pembrokeshire for the last couple of weeks. Could that be a symptom of impaired battery cooling? using E5 petrol makes no difference either.

Other things I've tried an wondered just how/why is the manual sport mode with the paddles. Briefly tried it, and thought it might just be an engine revs thing; but how is it supposed to work? And just why on a vehicle with a CVT

MPG is sensitive to so many things it's hard to say what the cause is. The wind could've been against you more than usual for all we know.

If you haven't given the filter a clean, it wouldn't be a bad shout to do it anyway. Especially if the rear driver's side is used a lot. For whatever reason, it isn't a service item so generally Lexus won't touch it until it's a problem.

Plus side? Hoover for the filter and some air to clear the fan out and it's good to go.

The downside? You're gonna have to get behind the boot lining to do it.

I wouldn't take much notice of the manual thing in all honesty... It's largely just for engine braking and holding revs when off throttle and the car overrides the 'gears' anyway. Think of it more as hill decent mode. I wouldn't use it for much more than a long hill decent.

[IS300FSPORT]

42MPG sounds like the norm your never going to consistently acheive diesel territory MPG figures. 

Only obvious call outs are dont carry unnecessary weight, check tyre pressures, go easy on the throttle but that soon becomes boring.

I stopped chasing MPG figures a few months after ownership, I genuinely don't know how people acheive 60+mpg figures over a full tank. To keep pace with traffic or driving it normal without holding traffic does hurt the figures (at least from my experience), the 2.5 engine is not great on economy but neither is it bad, if your coming from a diesel you will feel the MPG drop like I did. 

[Stever750]

I think I posted earlier that 40mpg was my target business mileage eco, do far it's doing that. Bizarrely it's more eco at 75-80 on the M4 than it is pooling at 40 ish around here locally. I guess no car is better on undulating B lanes than flat M-ways, but I would have thought that the regen and Battery energy would come into its own on such roads compared to conventional ice power. 

That said, really enjoying the ownership experience. It's a 1970s cocktail cabinet and humidor kind of car, but can slightly kick ***** when you need it to. 

Happy Easter to you all!

[TheMcSame]

33 minutes ago, Stever750 said:

I think I posted earlier that 40mpg was my target business mileage eco, do far it's doing that. Bizarrely it's more eco at 75-80 on the M4 than it is pooling at 40 ish around here locally. I guess no car is better on undulating B lanes than flat M-ways, but I would have thought that the regen and battery energy would come into its own on such roads compared to conventional ice power. 

That said, really enjoying the ownership experience. It's a 1970s cocktail cabinet and humidor kind of car, but can slightly kick ***** when you need it to. 

Happy Easter to you all!

You'd think so, but I think the biggest problem is that the car is too keen to boot itself out of EV mode to really yield the best benefits it can...

This and the inability to make progress at a reasonable pace in EV mode as a whole. There's definitely gains to be had by allowing the car to use more throttle in ev mode at low speeds so you can get up to like 15 MPH at a reasonable pace before the engine kicks in. It's a 140 HP motor supposedly (which also means there's almost 100 spare horses locked away given peak power is 223... I'm surprised there's no 'remap' service to unlock that honestly) so it's not like it lacks the power

I mean for me... Country road, urban and traffic lighted dual carriageway? I'd definetly stand to see some MPG improvements with an electric motor that'll get the ball rolling at a decent pace, because who wants to be toddling along slowly building up speed while cars behind are potentially approaching at 70? I think I managed to just brush 39MPG on the last run. Which probably isn't bad given the circumstances honestly... 

 

 

[Notamech]

In my experience the biggest thing affecting MPG on motorways is speed unfortunately.  On motorways i easily manage anywhere between 45-53 but i keep my speed between 60-65.  On trips where ive gone faster i.e 70+ its similar to what you are seeing. 

Most of my daily driving is short city driving and because for most of my 2 -3 mile trips the engine is constantly running trying to warm itself and the cabin i get an abysmal 24-34 depending on the weather. So in this case despite low speeds other factors such as the trip being short saps my MPG. So your MPG on B road journeys would also depend on factors like weather, your climate control temp, length of the trip, terrain type e.g. hilly vs flat and your speed. 

[Thackeray]

18 hours ago, Stever750 said:

Another refuel, trip said 42.3, app calculated 39.5 What's slightly bizarre is that the average dropped by around 3mpg after a 220 mile on the M4, followed by pootling around the lanes of Pembrokeshire for the last couple of weeks. Could that be a symptom of impaired battery cooling? using E5 petrol makes no difference either.

My average since 2017 is 42.25 mpg, calculated from one fill-up to the next. I've excluded the covid years when it was averaging mid-20s because I wasn't using the car much. Peak real mpg was around 50-54 mpg, always in August or September for a 300 mile motorway journey. I think the mpg might have benefitted from long motorway 50 mph speed restrictions. Incidentally, I never turn off the air conditioning. Expect to see better mpg as the weather improves.

The highest number I've seen on the car computer is 71 mpg after a 20 minute drive starting with a warm engine. I found it hard to believe and the only thing I could think of was that it must have been downhill all the way, even though from the car it looked like flat countryside. I checked on a map and sure enough, although it didn't look like it at the time, there was a gradual decline in altitude for the whole journey. It's a trip I've done more than once and fuel consumption is always much better than usual even though you don't notice the downhill effect while you're driving.

[Thackeray]

18 hours ago, Stever750 said:

Other things I've tried an wondered just how/why is the manual sport mode with the paddles. Briefly tried it, and thought it might just be an engine revs thing; but how is it supposed to work? And just why on a vehicle with a CVT

I think it's mostly just for fun. In a manual car you might change down to get more power for faster overtaking. You can simulate this for the same reason - higher revs gives more power, perhaps when you're about to overtake. But with this transmission you can get higher revs just by pressing the accelerator in a way that is not possible in a manual. In past years, journalists who didn't understand this described the transmission as being noisy. This is wrong. It's not the transmission that is noisy it's the engine, which like any other engine is noisy if you change down to the lowest available gear when the car is moving at speed. It's just that you can get maximum power in this transmission just by pressing the accelerator, rather than having to manually change down.

You can also use the paddles on a long descent of a hill. But I generally use the brakes in order to get maximum power regeneration. If the hill is not too steep you may be able to slow the car enough with a light touch of the brakes which will only use the motor-generators, rather than the brake pads, to feed electricity into the Battery. And when the Battery is full, the car will increase engine revs automatically to provide engine braking when the Battery can take no more electricity. Sometimes you might think the engine is running when in fact no fuel is being used but electricity is being drawn from the Battery and the motor-generators are turning the engine without petrol. This is done to reduce the charge in the Battery when it's close to the maximum.

[Stever750]

As I thought they're pretty much pointless! 

It sounds as though my car is wherr it should be mpg wise given how I drive it. Anything over 40 is a financial bonus for business use, at fast motorway cruising speeds, and so far that's been the case. 

I'll give the Battery air filter a clean later in the year when it's not constantly raining. I might have to wait a while for that day..... 

[wharfhouse]

41 minutes ago, Thackeray said:

I think it's mostly just for fun. In a manual car you might change down to get more power for faster overtaking. You can simulate this for the same reason - higher revs gives more power, perhaps when you're about to overtake. But with this transmission you can get higher revs just by pressing the accelerator in a way that is not possible in a manual. In past years, journalists who didn't understand this described the transmission as being noisy. This is wrong. It's not the transmission that is noisy it's the engine, which like any other engine is noisy if you change down to the lowest available gear when the car is moving at speed. It's just that you can get maximum power in this transmission just by pressing the accelerator, rather than having to manually change down.

You can also use the paddles on a long descent of a hill. But I generally use the brakes in order to get maximum power regeneration. If the hill is not too steep you may be able to slow the car enough with a light touch of the brakes which will only use the motor-generators, rather than the brake pads, to feed electricity into the battery. And when the battery is full, the car will increase engine revs automatically to provide engine braking when the battery can take no more electricity. Sometimes you might think the engine is running when in fact no fuel is being used but electricity is being drawn from the battery and the motor-generators are turning the engine without petrol. This is done to reduce the charge in the battery when it's close to the maximum.

In D the "gears" are designed for hill descent etc as above to aid engine braking. In S and Sport mode the paddles it gearshift sequential give 6 simulated "gears" that can be used more like a normal gearbox - they work but after a few plays with them didn't see much benefit other than getting ready for a quick acceleration like an overtake - though in practice mash the pedal to the Floor and whatever you're in the car seems to deliver max power from engine and Battery together anyway. 

[Stever750]

2 minutes ago, wharfhouse said:

In D the "gears" are designed for hill descent etc as above to aid engine braking. In S and Sport mode the paddles it gearshift sequential give 6 simulated "gears" that can be used more like a normal gearbox - they work but after a few plays with them didn't see much benefit other than getting ready for a quick acceleration like an overtake - though in practice mash the pedal to the Floor and whatever you're in the car seems to deliver max power from engine and battery together anyway. 

I've found sport mode plus full throttle works as good as you'll get for overtaking. It's a massive improvement over my wife's Auris in that respect, thank goodness. 

[Cesar]

On 2/18/2024 at 9:55 AM, wharfhouse said:

Yes that IS you tested does sound like it's not been well looked after which is a shame given such low mileage. It could probably all be sorted but if you need a car to start and use quickly for high mileages then you probably need to look elsewhere. I have to say that I always look forward to any journey in my IS as I know it will be relaxing and stress free - even accounting for the appalling driving that is around today! I genuinely wouldn't have kept it for the time I have otherwise.

Out of all the cars I've owned two have stood out. The first a 1997 E39 BMW 528i that I owned from new and did over 200k miles in across the UK and Europe - absolutely superb car that gave very little trouble (always dealer serviced) and that I always looked forwards to a long road trip in. And the second my current IS 300h that I put in the same category. 

I've had faster cars, bigger cars and all sorts but those are the two that I will always have a soft spot for. Not sure how many more years the IS 300h will be reliable for but I've seen reports of 250k miles in some and I've decided for the time being to keep it and see where that leads. It genuinely still drives like new at 144K miles. 

I've bought mine this year IS300H 2014 with 300k miles and drives smooth, the previous owner had done all services in main dealer. Hybrid Battery will need replacement soon that's all

[Mr_Groundhog]

22 hours ago, Cesar said:

I've bought mine this year IS300H 2014 with 300k miles and drives smooth, the previous owner had done all services in main dealer. Hybrid battery will need replacement soon that's all

how are the suspensions holding uup after so many Kms?

[wharfhouse]

22 hours ago, Cesar said:

I've bought mine this year IS300H 2014 with 300k miles and drives smooth, the previous owner had done all services in main dealer. Hybrid battery will need replacement soon that's all

How do you know the hybrid Battery will need replacing soon - have you had any errors being shown? If the hybrid health check has been carried out to schedule (which if it's been serviced by Lexus it should have been) then the Battery is warrantied for 15 years with unlimited mileage and so should be changed free of charge.