Is220d Fuel Economy Fixes?

[Scarlet Pimpernell]

OK guys - been on another run today. I can confirm now that the ECU Remap has made the car better to drive, but NOT more economical. In fact, I now see the histogram dive faster, and the car averaged a miserable 36.9mpg on a 276 mile motorway run today, all within legal limits. I reckon it would have been good for closer to 40mpg (or slightly over), considering there was some traffic, stop starts etc.

With the remap, you have to drive even gentler to get good economy, or so I'm finding.

WTS for my end of year report - thats right - I've had this car for a year now!

[Gareth]

I'm finding that I currently get 31mpg with frugral driving in urban conditions.

When I did two motorway runs of 30 miles I got an average up to 36mpg overall, which obviously meant great economy on that trip.

I did want to disagree with The Mole on something, though.

Running the engine on the turbo will not definitely mean better economy.

It doesn't so much "help it breathe" as it does "ram as much oxygen as it can in there", and more oxygen means more fuel.

The gain in performance isn't always quite proportional to the extra fuel used,

so whilst you get a 50% rise in performance you might get a 60% rise in consumption.

With my car I ran it at a steady 2500rpm, with no foot fluctuations on a steady road, at 40mph, IIRC.

I then changed up a gear, and ran it at ~1500rpm, same speed, no fluctuations of throttle.

I found that the average consumption goes straight up 20mph, roughly.

This is perfectly what I'd expect - turbos are there to give you a bigger bang. Whilst more oxygen provides for this, they are also mapped to provide more fuel as the exhaust gas runs lean, generally.

I hope I'm not wrong about all this ;)

[Scarlet Pimpernell]

I'm finding that I currently get 31mpg with frugral driving in urban conditions.

When I did two motorway runs of 30 miles I got an average up to 36mpg overall, which obviously meant great economy on that trip.

I did want to disagree with The Mole on something, though.

Running the engine on the turbo will not definitely mean better economy.

It doesn't so much "help it breathe" as it does "ram as much oxygen as it can in there", and more oxygen means more fuel.

The gain in performance isn't always quite proportional to the extra fuel used,

so whilst you get a 50% rise in performance you might get a 60% rise in consumption.

With my car I ran it at a steady 2500rpm, with no foot fluctuations on a steady road, at 40mph, IIRC.

I then changed up a gear, and ran it at ~1500rpm, same speed, no fluctuations of throttle.

I found that the average consumption goes straight up 20mph, roughly.

This is perfectly what I'd expect - turbos are there to give you a bigger bang. Whilst more oxygen provides for this, they are also mapped to provide more fuel as the exhaust gas runs lean, generally.

I hope I'm not wrong about all this ;)

I'm sure it the ECU runs all sorts of algorithms and arranges for a mix which is optimum, but you'r probably right!! More turbo, more air and fuel, less economy!

[Matus]

With my car I ran it at a steady 2500rpm, with no foot fluctuations on a steady road, at 40mph, IIRC.

I then changed up a gear, and ran it at ~1500rpm, same speed, no fluctuations of throttle.

I found that the average consumption goes straight up 20mph, roughly.

you don't need to run it at 2500 when driving on constant speed. That's why the consumption at 1500rpm was better - the power on 1500 revs is enough to move the car and maintain the speed, whilst at 2500rpm there is too much unnecessary power.

however

when accelerating and keeping the revs around 1500rpm means that the acceleration is slow even when flooring it (=injecting lot of fuel). Therefore it's better to keep the revs over 1.800rpm when accelerating.

[Gareth]

Matus,

Anything less than 1500 wouldn't have been able to maintain the speed... I didn't choose these rpms, they chose me ;)

[RSV Daz]

ok..ive been driving the car by changing up before the rev hits 2k and i must admit i am getting better fuel economy....but it still bugs me that the car is over idling even well into a journey..20 mins plus..surely this cant be right?

[Matus]

the Mole wrote in other topic that it is normal, because of the emisions.

[VrmmVrmm]

ok..ive been driving the car by changing up before the rev hits 2k and i must admit i am getting better fuel economy....but it still bugs me that the car is over idling even well into a journey..20 mins plus..surely this cant be right?

During the early part of any journey have you the fan on?

If you switch it off when standing in traffic the revs drop almost 500 rpm.

I've noticed this only recently.

Has to save fuel!

Works for me. My tank averages 6.3 litres per 100klm...44.8 mpg nearly all the time now...thats what it supposed to achieve. But you're quite right it does run for a while and maybe for too long not sure myself how long it should stay on.

Happy motoring...its still a great car!

[SiWhite]

The car achieved a staggering (for it) average of 47.7mpg on my trip back from Newcastle to the Midlands today. That includes the urban bits at either end of the journey.

[Gareth]

Works for me. My tank averages 6.3 litres per 100klm...44.8 mpg nearly all the time now...thats what it supposed to achieve. But you're quite right it does run for a while and maybe for too long not sure myself how long it should stay on.

Happy motoring...its still a great car!

What's mileage has yours done.

Mine's creeping up steadily, now to 34mpg tank average, but I'm still at under 500 miles.

G

[VrmmVrmm]

Works for me. My tank averages 6.3 litres per 100klm...44.8 mpg nearly all the time now...thats what it supposed to achieve. But you're quite right it does run for a while and maybe for too long not sure myself how long it should stay on.

Happy motoring...its still a great car!

What's mileage has yours done.

Mine's creeping up steadily, now to 34mpg tank average, but I'm still at under 500 miles.

G

Just over 5000 klms...3200 miles and settling at 44.8 mpg better than I had expected when taking into account the experience of other owners. I do a few fairly long runs around the weekends but other than that its 12 miles to work and 12 miles home 5 days a week. :D

[The Mole]

I'm finding that I currently get 31mpg with frugral driving in urban conditions.

When I did two motorway runs of 30 miles I got an average up to 36mpg overall, which obviously meant great economy on that trip.

I did want to disagree with The Mole on something, though.

Running the engine on the turbo will not definitely mean better economy.

It doesn't so much "help it breathe" as it does "ram as much oxygen as it can in there", and more oxygen means more fuel.

The gain in performance isn't always quite proportional to the extra fuel used,

so whilst you get a 50% rise in performance you might get a 60% rise in consumption.

With my car I ran it at a steady 2500rpm, with no foot fluctuations on a steady road, at 40mph, IIRC.

I then changed up a gear, and ran it at ~1500rpm, same speed, no fluctuations of throttle.

I found that the average consumption goes straight up 20mph, roughly.

This is perfectly what I'd expect - turbos are there to give you a bigger bang. Whilst more oxygen provides for this, they are also mapped to provide more fuel as the exhaust gas runs lean, generally.

I hope I'm not wrong about all this ;)

But on a steady throttle position, the turbo spins slowly pruducing very little boost, just enough to run efficiently without labouring the engine which is what causes the vibration when you accellerate under 2krpm.

Only when you put your foot down does the turbo spool up to speed to give you the extra power / fuel used - hence turbo lag.

I've run my diesel for a while now and have averaged 37 mpg with a mix of gentle driving.

There are three problems.

1) Engine is rough when off boost causing 6th to vibrate and generally be unpleasent to use under 2krpm. The ecu mod helps a great deal, but the problem still exists.

2) The gear ratios are hopeless. Way too tall and wide spaced given the power band and lack of engine flexibility - see problem 1.

3) It is not an economical engine.

All the above points are attributed to lowering emissions for Euro V.

Just so you are all aware, Lexus have commited to having an 'ALL HYBRID' showroom by 2014. No petrol only, no diesel, just hybrid.

Why didn't they do a hybrid IS straight away? Not enough space for the batteries used at present. As soon as lithium polymer batteries can be made safe enough, watch this space.

[mradford]

The Mole

Forgive me for asking a general question on this thread but seems like a good time to ask and you're as good as any!

I'm planning on getting an IS in the new future (stock market permitting!) and drove a SE last year without MM. The MM is a must for me but I'm torn on the options. Everyone seems to suggest the SE-L Auto. Are they right? I like the manual but am not fussed about swapping across.

Also, how much haggling can be done on the Approved pre-owned?!

Thanks

Martin

[Scotty38]

The car achieved a staggering (for it) average of 47.7mpg on my trip back from Newcastle to the Midlands today. That includes the urban bits at either end of the journey.

Did very similar (Nottingham-ish to Newcastle and back again) yesterday and achieved 37.7.....Not quite so staggering

[The Mole]

The Mole

Forgive me for asking a general question on this thread but seems like a good time to ask and you're as good as any!

I'm planning on getting an IS in the new future (stock market permitting!) and drove a SE last year without MM. The MM is a must for me but I'm torn on the options. Everyone seems to suggest the SE-L Auto. Are they right? I like the manual but am not fussed about swapping across.

Also, how much haggling can be done on the Approved pre-owned?!

Thanks

Martin

Only go for SE-L if you want / need the extra equipment, it won't be worth much more if any than an SE come resale.

MM is always worth getting IMHO. Sat Nav makes a car much more desireable to the used buyer, especially with the new phone laws etc.

Auto every time.

Used approved? - Depends on too many factors - anything form zero to several hundred pounds, but there are too many factors to consider to give a meaningful answer I'm affraid.

Any dealer offering more than a £700 - £800 'deal' on a used car has over priced it to start with, or employs muppets for sales people.

[mradford]

Brilliant, thank you.

[Gareth]

For me the SE-L was an easy choice - I wanted too much of the stuff on it.

I was considering the sport on the diesel, but then went against that because I'm not getting this car to be sporty, and I'd miss the upgraded seats and wood.

I would have liked the 250 auto, a lot, but wasn't going that way this time.

[JANUS]

Hello,

i come from germany and i read here in this topic about an upgrade for the Motor-ECU of the IS220d (" mole" says, it´s available since mid-february in UK).

My questions:

1. Is it an update (software) or an switch of the ECU?

2. Can give anybody more details of this upgrade? The describtion, ect. (version-number...)

Background: There is no dealer in dark-germany, there know anything about an upgrade, also LEXUS-GERMANY don´t give further information about it. :tsktsk:

And so, i will ask my dealer directly, but i need more information (version....)

Thanks a lot

[The Mole]

Hello,

i come from germany and i read here in this topic about an upgrade for the Motor-ECU of the IS220d (" mole" says, it´s available since mid-february in UK).

My questions:

1. Is it an update (software) or an switch of the ECU?

2. Can give anybody more details of this upgrade? The describtion, ect. (version-number...)

Background: There is no dealer in dark-germany, there know anything about an upgrade, also LEXUS-GERMANY don´t give further information about it. :tsktsk:

And so, i will ask my dealer directly, but i need more information (version....)

Thanks a lot

It is a 'plug in' software update. I'll try and find the ref number for you.

[Scarlet Pimpernell]

Mole - can you also check if ti will reset itself, and if so, under what circumstances (e.g disconnection of battery) - I have called 2 dealers - one said it would, the other said it wouldn't...

[The Mole]

Mole - can you also check if ti will reset itself, and if so, under what circumstances (e.g disconnection of battery) - I have called 2 dealers - one said it would, the other said it wouldn't...

No, it won't reset itself - it is a permanent change to the software - just the same way that if you turn your computer off, it doesn't change back to Windows 3.1.... :)

The upgrade is only available in the UK as the 5th injector issue has only occured in the UK. The fringe bennefits to running are just a bonus to what the mod is actually designed to do.

[Scarlet Pimpernell]

Mole - can you also check if ti will reset itself, and if so, under what circumstances (e.g disconnection of battery) - I have called 2 dealers - one said it would, the other said it wouldn't...

No, it won't reset itself - it is a permanent change to the software - just the same way that if you turn your computer off, it doesn't change back to Windows 3.1.... :)

The upgrade is only available in the UK as the 5th injector issue has only occured in the UK. The fringe bennefits to running are just a bonus to what the mod is actually designed to do.

You're a star

[The Mole]

One thing I have noticed and can't find a single reason that stands up logically is that whenever we fit 18" accessory wheels, the economy drops by up to 5mpg overall!

Same rolling diameter, same width of tyre, same offset etc - work that one out!

[Gareth]

Good thing I didn't get them then!

I was actually thinking shortly after I got it that I thought I should have.

[Scarlet Pimpernell]

Good thing I didn't get them then!

I was actually thinking shortly after I got it that I thought I should have.

Aerodynamics?