Is220d Fuel Economy Fixes?

[Gareth]

Yes, all diesels will have the mod done, without asking. They will come from the factory like that very soon.

Whether you get better mpg or not will depend on how much you drive at lower revs where more of the improvement will be felt.

Is your username any sort of hint at how you know all this/ :winky:

[ColinBarber]

Some information for you all, in no particular oder.

1) Luxus Japan didn't want to make a diesel, but eventually and reluctantly agreed after intense lobbying from Lexus Europe.

3)The reason there is no auto is that there is no rear wheel drive auto trans anywhere in the Toyota group that would handle the torque, and they would never use anyone elses trans. They wouldn't sell enough to justify the developmental costs of an all new auto trans just to fit in one model sold in very samll numbers.

Lexus don't make the engine, it's a Toyota engine that is used in a few different models. The amount of money spent on development would be based on sales figures for all models not just the IS220d.

The auto box from the LS430 and GS430 can easily handle the torque of the IS220d engine. Toyota don't make any of their auto boxes anyway, they leave that to their parnter Aisin AW. Toyota have also used other manufactures in the past for gearboxes, Getrag being one.

[Gareth]

Lexus do not update the ecu automatically on new cars.

They offered to do it automatically on mine since I asked.

[Matus]

You shouldn't have to drive that lightly to achieve good MPG. You can drive a VW Golf or Passat at 80mph +, taking it up to at least 3,000 rpm in each gear and still get 50mpg+

yes, but. those cars exceed more than 10times in some aspect of emissions and because of the noise you can't hear own voice...

that are just principles of PD (pumpe duse) vs CR (common rail). PD is more economical with high power outputs, but are more rough, loud and the power/torque curve is steep. CR has better power delivery, it's softer and quieter, but this is paid out by the consumption

The Mole - thanks for informations.

[Harrydavy]

The Mole

Thanks for the information, it makes very interesting reading. At least the ecu mod should help with low down torque.

Harrydavy

Although you said fuel consumption had not improved, what about improved low rev performance?

Thanks

Not improved, its worse! But following reading other posts, I have been to sunny Clackton today, 310 mile round trip and tried the change gear @ 2000 mile trick. Shock horror! it can be done until you get to 6th gear. Very boring drive and only pushes the mpg upto 34.

Scarey stuff from the mole though! Wonder if it would stand up in court?? :shutit:

[The Mole]

Yes, all diesels will have the mod done, without asking. They will come from the factory like that very soon.

Whether you get better mpg or not will depend on how much you drive at lower revs where more of the improvement will be felt.

Is your username any sort of hint at how you know all this/ :winky:

Yes...

[The Mole]

Some information for you all, in no particular oder.

1) Luxus Japan didn't want to make a diesel, but eventually and reluctantly agreed after intense lobbying from Lexus Europe.

3)The reason there is no auto is that there is no rear wheel drive auto trans anywhere in the Toyota group that would handle the torque, and they would never use anyone elses trans. They wouldn't sell enough to justify the developmental costs of an all new auto trans just to fit in one model sold in very samll numbers.

Lexus don't make the engine, it's a Toyota engine that is used in a few different models. The amount of money spent on development would be based on sales figures for all models not just the IS220d.

The auto box from the LS430 and GS430 can easily handle the torque of the IS220d engine. Toyota don't make any of their auto boxes anyway, they leave that to their parnter Aisin AW. Toyota have also used other manufactures in the past for gearboxes, Getrag being one.

Yes, it is a Toyota engine, but the engine isn't anything to do with the development costs of the gearbox.

Yes, the GS/LS trans can cope with the torque, but they cannot cope with the long life fatigue that the power pulse gennerated by the higher compression diesel engine creates. Also, all the ratios woud need to be altered to meet the torque curve and lower revs of the diesel engine, although this is a minor point.

The key point is that any box used needs to be RWD, and there isn't a trans available elsewhere in the company that will do the job in termes of strength, longevity, size etc.

All I am doing is trying to answer some questions with accurate information.

Please carry on debating it if your not happy, but the information will stay the same.

[Scarlet Pimpernell]

This is all fine and dandy....

1) Some of us remember "The Mole" from last year - he disappeared as soon as the cars started to rattle, and the poor consumption figures hit the streets. Now he's back, to give us good news...

2) I feel totally duped into buying a car that feels, at times, compromised. Lexus charge full ticket for this car here, yet Mr Mole almost makes you feel that Lexus couldn't afford to make an automatic or a new gearbox 'cos it's rear wheel drive. Come on, it's just about the biggest car maker in the world and Lexus branding is focused on Customer Satisfaction. Well explain that one...may be Lexus really don't want to sell the car here and in Europe, but feel they have to, and the UK's Customer Satisfaction is better served by the opposition who go out of there way to make Auto's, AWD, Estates etc...and maybe that's why they sell more of them!

Why does Lexus feel that everything has to be already developed within group? Why can't they treat the Lexus IS in the same way as the GS, or LS? I know it's the first rung of the ladder into Lexus, but many of us could have bought a GS for a couple of extra grand...I think it's 'cos Lexus's development budget is available if your project in Toyota MG says "Hybrid" and not "Diesel". It is such a compromised attempt!

3) It doesn't make me feel good to know that my Lexus, with all the problems I've had in the past is effectively made up with bits from trucks. The rationale of the extra torque...well it's feeble, especially when you consider that many other makers offer 2, 3 even 4 different types and sizes of Diesel engines in their ranges, ranging from 4,6, 8 and even 10 cylinder diesels!

4) As a private buyer and someone who cares about the environment, I bought a diesel not just for the CO2, but for economy too. And this being lauded as the cleanest made me want it even more. More so than a hybrid, which for me is just too complex! Well it is hard work getting over 42-45 mpg on a run. It can be done, but boy do you need discipline. You can get similar figures from a petrol BMW320i if you try as hard!

5) The gearing makes it uncomfortable at 70. 5th feels too low and it wants sixth, but 6th too tall at motorway speeds, and fuel economy is more volatile than in a petrol car. Just watch the histogram on Current MPG as you go up and down hills in any gear...

6) almost a year on, I do reflect on some of the press stories of the car when it was launched. I dare say many were right...not all, but some...

The car itself is good, but the compromises in the "drive" tarnish the overall experience. Especially in the UK, where you're constantly having to lane hop.

I've just done 610 miles (mainly motoray) this week in mine. It runs better than ever, on a single tank of Diesel, and the trip showed I had 10 miles worth of fuel when I filled up. That's the furthest I've ever taken it on a single tank.

The problem is that I had to drive it so gently, and keep the horses down to a trot.

The engine is smoother than ever, refinement overall has improved a lot, but somehow it feels lacking. I dunno, maybe it's just me...but I have never felt like this about any other car in over 400,000 miles of driving.

PS - what the 'eck - it goes in for service #1 this month, I dare say it'll have it's ECU mod'd!

[Harrydavy]

I've just done 610 miles (mainly motoray) this week in mine. It runs better than ever, on a single tank of Diesel, and the trip showed I had 10 miles worth of fuel when I filled up. That's the furthest I've ever taken it on a single tank.

Surely not on one tank???? :o :o :o

[Scarlet Pimpernell]

I've just done 610 miles (mainly motoray) this week in mine. It runs better than ever, on a single tank of Diesel, and the trip showed I had 10 miles worth of fuel when I filled up. That's the furthest I've ever taken it on a single tank.

Surely not on one tank???? :o :o :o

Oh yes :D but you have to remember that my old A4 went 800 miles on 68 litres!

I change between 2000-2500ish revs, depending on the gear, speed and incline. So 1st to 2nd is typically upto 2500ish RPM, 4th to 5th will be 2000ish RPM. And I tend to get up to speed as quickly and smoothly as possible - a trick VBH mentioned on a 5th gear programme a couple of years ago.

[Harrydavy]

I've just done 610 miles (mainly motoray) this week in mine. It runs better than ever, on a single tank of Diesel, and the trip showed I had 10 miles worth of fuel when I filled up. That's the furthest I've ever taken it on a single tank.

Surely not on one tank???? :o :o :o

Oh yes :D but you have to remember that my old A4 went 800 miles on 68 litres!

I change between 2000-2500ish revs, depending on the gear, speed and incline. So 1st to 2nd is typically upto 2500ish RPM, 4th to 5th will be 2000ish RPM. And I tend to get up to speed as quickly and smoothly as possible - a trick VBH mentioned on a 5th gear programme a couple of years ago.

The most I've got is 460!! :duh:

Will try your method at next fill up.

Due to go to Newcastle next week so will see!

[Scarlet Pimpernell]

I've just done 610 miles (mainly motoray) this week in mine. It runs better than ever, on a single tank of Diesel, and the trip showed I had 10 miles worth of fuel when I filled up. That's the furthest I've ever taken it on a single tank.

Surely not on one tank???? :o :o :o

Oh yes :D but you have to remember that my old A4 went 800 miles on 68 litres!

I change between 2000-2500ish revs, depending on the gear, speed and incline. So 1st to 2nd is typically upto 2500ish RPM, 4th to 5th will be 2000ish RPM. And I tend to get up to speed as quickly and smoothly as possible - a trick VBH mentioned on a 5th gear programme a couple of years ago.

The most I've got is 460!! :duh:

Will try your method at next fill up.

Due to go to Newcastle next week so will see!

I did that a few weeks ago - to Newcastle - believe it or not it is mainly uphill all the way there! I got low 40's and improving until I arrived, and on the way back it shot up to over 48mpg...see how you fair...!

[Harrydavy]

I've just done 610 miles (mainly motoray) this week in mine. It runs better than ever, on a single tank of Diesel, and the trip showed I had 10 miles worth of fuel when I filled up. That's the furthest I've ever taken it on a single tank.

Surely not on one tank???? :o :o :o

Oh yes :D but you have to remember that my old A4 went 800 miles on 68 litres!

I change between 2000-2500ish revs, depending on the gear, speed and incline. So 1st to 2nd is typically upto 2500ish RPM, 4th to 5th will be 2000ish RPM. And I tend to get up to speed as quickly and smoothly as possible - a trick VBH mentioned on a 5th gear programme a couple of years ago.

The most I've got is 460!! :duh:

Will try your method at next fill up.

Due to go to Newcastle next week so will see!

I did that a few weeks ago - to Newcastle - believe it or not it is mainly uphill all the way there! I got low 40's and improving until I arrived, and on the way back it shot up to over 48mpg...see how you fair...!

If I managed that, I would never bother Leicester again!! And stop looking at 320D!!

Leicester are having my car in again mid march to do further tests - so we will see but after that I will be taking thing further.

[The Mole]

This is all fine and dandy....

1) Some of us remember "The Mole" from last year - he disappeared as soon as the cars started to rattle, and the poor consumption figures hit the streets. Now he's back, to give us good news...

2) I feel totally duped into buying a car that feels, at times, compromised. Lexus charge full ticket for this car here, yet Mr Mole almost makes you feel that Lexus couldn't afford to make an automatic or a new gearbox 'cos it's rear wheel drive. Come on, it's just about the biggest car maker in the world and Lexus branding is focused on Customer Satisfaction. Well explain that one...may be Lexus really don't want to sell the car here and in Europe, but feel they have to, and the UK's Customer Satisfaction is better served by the opposition who go out of there way to make Auto's, AWD, Estates etc...and maybe that's why they sell more of them!

Why does Lexus feel that everything has to be already developed within group? Why can't they treat the Lexus IS in the same way as the GS, or LS? I know it's the first rung of the ladder into Lexus, but many of us could have bought a GS for a couple of extra grand...I think it's 'cos Lexus's development budget is available if your project in Toyota MG says "Hybrid" and not "Diesel". It is such a compromised attempt!

3) It doesn't make me feel good to know that my Lexus, with all the problems I've had in the past is effectively made up with bits from trucks. The rationale of the extra torque...well it's feeble, especially when you consider that many other makers offer 2, 3 even 4 different types and sizes of Diesel engines in their ranges, ranging from 4,6, 8 and even 10 cylinder diesels!

4) As a private buyer and someone who cares about the environment, I bought a diesel not just for the CO2, but for economy too. And this being lauded as the cleanest made me want it even more. More so than a hybrid, which for me is just too complex! Well it is hard work getting over 42-45 mpg on a run. It can be done, but boy do you need discipline. You can get similar figures from a petrol BMW320i if you try as hard!

5) The gearing makes it uncomfortable at 70. 5th feels too low and it wants sixth, but 6th too tall at motorway speeds, and fuel economy is more volatile than in a petrol car. Just watch the histogram on Current MPG as you go up and down hills in any gear...

6) almost a year on, I do reflect on some of the press stories of the car when it was launched. I dare say many were right...not all, but some...

The car itself is good, but the compromises in the "drive" tarnish the overall experience. Especially in the UK, where you're constantly having to lane hop.

I've just done 610 miles (mainly motoray) this week in mine. It runs better than ever, on a single tank of Diesel, and the trip showed I had 10 miles worth of fuel when I filled up. That's the furthest I've ever taken it on a single tank.

The problem is that I had to drive it so gently, and keep the horses down to a trot.

The engine is smoother than ever, refinement overall has improved a lot, but somehow it feels lacking. I dunno, maybe it's just me...but I have never felt like this about any other car in over 400,000 miles of driving.

PS - what the 'eck - it goes in for service #1 this month, I dare say it'll have it's ECU mod'd!

Yup, still here..... I hid in my hole for a while until the heat died down a bit......

On a serious note though, please be aware that although you may not like what I report, I will only tell you how it is. I have no axe to grind on either side of the fence.

TMC are as you say are a huge company with Lexus being a small division. You'd be amazed at how in some instances, they opperate quite independantly of each other.

Yes, in some areas, the diesel is compromised - in our case the transmission used isn't ideal and due to the CO2 issue, although with Euro 5 round the corner, this should allow the use of more appropriate gearing when the new emissions regs show the car to be comparitively 'ultra clean' - nox, sulphur, particulates etc.

Trust me - as soon as the competition are forced to comply with euro 5, their mpg figures will tumble - I know this for a fact as I've spoken to a senior development engineer for a major German car manufacturere who are currently scratching their heads over the matter.

Other manufacturers compromise too, more that you would think.

I still maintain that the IS is a very smooth, quiet, quality, safe and well equipped car.

As I say, all I can give you are the facts as I get them, but I don't want to get into a debate over what I cannot change.

I'll keep quiet if that is your preference, but there may be people that would like to know reasons for things rather than PR answers from service departments?

[Scarlet Pimpernell]

Actually Moley, it's good to have you back! Not just so that we can tomato you every now and again, but actually because you are one that does come on here and tell us like it is. Good on you fella.

It's not personal, and I like many do welcome your input and info.

It is a very refined car, no question, and like I say it's good, wows you, but over time the niggles all amount to a "considerable niggle"...if you know what I mean.

[The Mole]

Actually Moley, it's good to have you back! Not just so that we can tomato you every now and again, but actually because you are one that does come on here and tell us like it is. Good on you fella.

It's not personal, and I like many do welcome your input and info.

It is a very refined car, no question, and like I say it's good, wows you, but over time the niggles all amount to a "considerable niggle"...if you know what I mean.

No worries.

I know what you mean though. As soon as Euro 5 comes into force next year, we can hopefully get a better final drive ratio somwhere in the middle betweenthe sport and the base/SE. That will cure all the 6th gear issues, flexibility, vibration etc. Along with the ecu mod we now have, will leave us with the car that the engineers wanted to give us in the first place, rather than the compromise we have now, just so it satisfies the company car drivers pocket.

Personally, I think we shouldn't have even bothered with a diesel in the first place, even though I get my new one on Monday...... Only for the same reason that I hope Ferrari don't ever make and estate.

[SiWhite]

I know what you mean though. As soon as Euro 5 comes into force next year, we can hopefully get a better final drive ratio somwhere in the middle betweenthe sport and the base/SE. That will cure all the 6th gear issues, flexibility, vibration etc. Along with the ecu mod we now have, will leave us with the car that the engineers wanted to give us in the first place, rather than the compromise we have now, just so it satisfies the company car drivers pocket.

That's an interesting thought. I presume owners will have to ask for the final drive ratio to be 'fixed' after Euro 5? I can't imagine that it'll be a routine upgrade / change like the ECU change.

[Harrydavy]

I know what you mean though. As soon as Euro 5 comes into force next year, we can hopefully get a better final drive ratio somwhere in the middle betweenthe sport and the base/SE. That will cure all the 6th gear issues, flexibility, vibration etc. Along with the ecu mod we now have, will leave us with the car that the engineers wanted to give us in the first place, rather than the compromise we have now, just so it satisfies the company car drivers pocket.

That's an interesting thought. I presume owners will have to ask for the final drive ratio to be 'fixed' after Euro 5? I can't imagine that it'll be a routine upgrade / change like the ECU change.

I assume that will not be free but chargable??

[Matus]

I know what you mean though. As soon as Euro 5 comes into force next year, we can hopefully get a better final drive ratio somwhere in the middle betweenthe sport and the base/SE. That will cure all the 6th gear issues, flexibility, vibration etc. Along with the ecu mod we now have, will leave us with the car that the engineers wanted to give us in the first place, rather than the compromise we have now, just so it satisfies the company car drivers pocket.

That's an interesting thought. I presume owners will have to ask for the final drive ratio to be 'fixed' after Euro 5? I can't imagine that it'll be a routine upgrade / change like the ECU change.

I assume that will not be free but chargable??

it looks like an easy fix. Basically you need to change one sprocket-wheel in the differential and reprogramm ECU to show the correct speed.

BUT

-the differential may be sealed in special way and maybe it won't be possible to seal it again like in factory

-the acces to the differential may be difficult

etc.

If it will be possible, I don't see that there will be less work than 10 hours + count some sealings + sprocket wheel. Count it together and - would you pay for it?

[SiWhite]

I know what you mean though. As soon as Euro 5 comes into force next year, we can hopefully get a better final drive ratio somwhere in the middle betweenthe sport and the base/SE. That will cure all the 6th gear issues, flexibility, vibration etc. Along with the ecu mod we now have, will leave us with the car that the engineers wanted to give us in the first place, rather than the compromise we have now, just so it satisfies the company car drivers pocket.

That's an interesting thought. I presume owners will have to ask for the final drive ratio to be 'fixed' after Euro 5? I can't imagine that it'll be a routine upgrade / change like the ECU change.

I assume that will not be free but chargable??

it looks like an easy fix. Basically you need to change one sprocket-wheel in the differential and reprogramm ECU to show the correct speed.

BUT

-the differential may be sealed in special way and maybe it won't be possible to seal it again like in factory

-the acces to the differential may be difficult

etc.

If it will be possible, I don't see that there will be less work than 10 hours + count some sealings + sprocket wheel. Count it together and - would you pay for it?

Yes, I think I probably would. Just to get a (more) usable 6th gear.

[The Mole]

I know what you mean though. As soon as Euro 5 comes into force next year, we can hopefully get a better final drive ratio somwhere in the middle betweenthe sport and the base/SE. That will cure all the 6th gear issues, flexibility, vibration etc. Along with the ecu mod we now have, will leave us with the car that the engineers wanted to give us in the first place, rather than the compromise we have now, just so it satisfies the company car drivers pocket.

That's an interesting thought. I presume owners will have to ask for the final drive ratio to be 'fixed' after Euro 5? I can't imagine that it'll be a routine upgrade / change like the ECU change.

I assume that will not be free but chargable??

it looks like an easy fix. Basically you need to change one sprocket-wheel in the differential and reprogramm ECU to show the correct speed.

BUT

-the differential may be sealed in special way and maybe it won't be possible to seal it again like in factory

-the acces to the differential may be difficult

etc.

If it will be possible, I don't see that there will be less work than 10 hours + count some sealings + sprocket wheel. Count it together and - would you pay for it?

Forget about it.

If they do change the final drive, it will be treated as 'on-going product improvement' - in the same way as new sat nav software is, or going from a 4 to a 5 speed auto box, or upgrading the RX300 to a RX350.

It won't be a cae of "here's a fix for that problem", it will be more like " The latest new IS diesel drives even better now..."

[Steken]

Hi all. Just thought I would add my comments to the list - perhaps I might add some balance??

This is my third Lexus, coming after 2 IS200's, the last being the LE. I got it the 220D mid January and was generally quite happy...but the vibrating mirror, and hard to figure gear ratios.

Initially, like others have posted, I found the car very sluggish low down - actually described pulling out of a junction as being "chug-chug-vroom!". Sixth gear was unuseable below 80mph, and fuel economy was in low 30's. Economy isn't my real concern as company pay for fuel - in case you wonder, they penalise us for having petrol cars!!

Having done about 1500 miles I took it into Lexus Bolton to replace some trim damaged before delivery, while it was there they said they would upgrade the ECU and said it may cure the turbo lag low down and smooth out the engine. I will add they offered to do this, I didn't ask! (Always been a v good dealership, recommended!) As a note they said they had only done this mod on one other car and didn't really know what the full effects of it were - they said they had only received this mod from Lexus mid-Feb.

Having driving the car home I phoned the dealership to ask exactly what they had done to my car - it was fantastic! From a stand start it now pulls positively and smoothly....through all gears! 6th gear is now useable at 70mph, useable being mirror wobble is not too bad not to have vision! Fuel economy has increased by a little over 3mpg, last tank 37.3mpg - and we should bear in mind I have only done 1600 miles so the engine is still 'tight'.

I know many more will disagree, but I am quite happy with this car following the ECU upgrade. If you haven't had this I would strongly advise you do so as I have never experienced such a change in a car before! I compared it to the dealer as feeling as if they had changed the gearbox!

Finally, though I did say to the dealer that due to the massive difference this mod makes then surely they should recall all cars for the upgrade as a PR excercise.

[VrmmVrmm]

Hello again,

Did another fairly long run on Saturday 240 miles round trip...5.6 litres per 100 klms thats 50 mpg. Just over 4000 klms now on the clock. The country roads I was driving on have a 50 mph limit...up down round right round left etc...typical. I was able to keep at 50 mph @1600 revs 5th gear and drove for miles with clear road ahead no gear changing at one point for about 5 miles the consumption dropped to 4.8 litres per 100 klms THAT'S a whopping 59 mpg. In order for the average reading to drop to that low consumption level you understand it must have been achieving economy well below the 4.8 litres maybe as little as the magic gallon 4.546 litres. This car has to be driven differently...any petrol owner jumping into a IS220D is going to get crap economy IF they attempt to drive it like their previous petrol engined car. For 80 miles of this journey I would have been on better roads driving at 60 mph @1900 revs 5th gear.

The problem with the calculator is that if you are stood at lights or in traffic the consumption is straight up to MAX ...any length of time in traffic therefore eats away your economy. I must admit I was not held up at any stage for very long...but then again the test bed which delivered the urban and extra urban figures probably didn't have traffic lights to deal with either. My average since I got the car...mixed driving and mixed journey lengths is currently 6.7 litres per 100 klms that's 42.2 mpg and falling. I too had to learn how to drive it and was at 7.8 litres for the first two weeks. Settled down now learning its perculiarities and winning.

Comments on the turbo lag...yes I too notice a lag but what about the next 3 or 4 secs when the car takes off and hurtles you at blistering pace neatly ahead of that articulated lorry that was blasting you with spray and crud....give the car a break its doing everything I ask it ... and will for you...so long as I ask it nicely.

[Harrydavy]

I know what you mean though. As soon as Euro 5 comes into force next year, we can hopefully get a better final drive ratio somwhere in the middle betweenthe sport and the base/SE. That will cure all the 6th gear issues, flexibility, vibration etc. Along with the ecu mod we now have, will leave us with the car that the engineers wanted to give us in the first place, rather than the compromise we have now, just so it satisfies the company car drivers pocket.

That's an interesting thought. I presume owners will have to ask for the final drive ratio to be 'fixed' after Euro 5? I can't imagine that it'll be a routine upgrade / change like the ECU change.

I assume that will not be free but chargable??

it looks like an easy fix. Basically you need to change one sprocket-wheel in the differential and reprogramm ECU to show the correct speed.

BUT

-the differential may be sealed in special way and maybe it won't be possible to seal it again like in factory

-the acces to the differential may be difficult

etc.

If it will be possible, I don't see that there will be less work than 10 hours + count some sealings + sprocket wheel. Count it together and - would you pay for it?

Having had twelve months with a unsatisfactrory car (poss mis-sold!) & 35k miles @ 31mpg. 10 hours seems a drop in the ocean. Would you pay or can you nip round & fix mine

[Scarlet Pimpernell]

So mine did have the ECU modification, referred to as:

"Engine ECU Remap" on the itemised invoice

Well well...Maybe it's psychological...

Initial responses: The car feels much more eager to shoot off at the line. It's as if the torque/turbo kicks in earlier, much earlier, but in a fashion that stops you from booting the accelerator at junctions to make a clean getaway. It's almost to Sport specifications - and so I would love to know if any Sport drivers have had the mod done...???

Just completed a journey to the pumps, to fill up, and an errand in town, all town driving, and 28.5mpg including 17.8 miles total. So that's no huge improvement, but boy the car feels a lot livelier!

I'm impressed by it - seems to have made the car enjoyable to drive now!

At the end of the day, and in hindsight, Lexus cannot just develop a ECU remap to fix everything as it will potentially change the CO2 figures, Company car tax thresholds, possibly a re-test to perform against the government guidelines etc, so they need to tread carefully. I suspect that if Lexus are serious about the diesel, then as Moley says, expect a major enhancement with revised Co2 figures etc in the short to medium term.

*** knows what that'll do our used values of the earlier Diesels...

In the meantime, I defo think mine has improved, but tomorrow will be a long run up "norf" and an opportunity to see if I can better 42mpg without killing the hamster pedalling in the engine compartment!