Erratic Power Delivery

[jonnyboy]

I recently returned my IS220d to Lexus so that they could investigate and hopefully cure the erratic power delivery. They re-mapped the ECU claiming that it would “feel like a new car” but I noticed very little change, if anything at all, to the way the engine performs.

The engine delivers almost no power below 2,00RPM, making it very difficult to pull away from a standing start in a hurry.

Example: I have found this unfortunate trait rather dangerous, especially when attempting to join a busy road or roundabout. If the revs to drop below 2,000RPM, the engine immediately bogs down leaving you having to frantically slip the clutch in order to build the revs back up to a level where the engine actually relinquishes some power. As well as being dangerous, this is not very dignified and cannot be much good for the clutch either.

Being an experienced driver and having owned and driven numerous 6-speed turbo diesels, I would say that the 1st gear ratio is simply too high for the job.

Another example: Try driving at exactly 30MPH on the flat then depressing the accelerator to the floor when you reach a derestricted section of road. With my car it takes a full 3 seconds before ANY change in acceleration is felt. What with the power only being delivered from 2,000PRM onwards, when driving in 3rd gear at 30MPH the engine is just below this critical speed ensuring this numb and rather frustrating response on attempting to accelerate.

Having also experienced problems with the useless 6th gear (see my previous post), I can only deduce that, when Lexus changed the final drive in an effort to make a distinction between the “Sport” model and the rest of the range, they have upset the gear ratios to the point that they are now not really practical for the job.

In addition to this, there is a subtle overrun which occurs when gently backing off the accelerator e.g. when moving slowly through traffic, which makes the car lurch forward in a rather embarrassing manner.

I can honestly say that I have never driven a turbo diesel which such strange and un-diesel like power delivery. Where I would normally hope to enjoy the low-down grunt of a torquey diesel engine, I instead find myself having to endure the quirky power delivery which, strangely enough, is not unlike that of the very first car I owned some twelve years ago, a Mazda 626 with a 1.8 petrol engine. Believe it or not I actually got better fuel economy from the Mazda!

Lexus have said that there is no solution to this problem. I mentioned the possibility of changing the injectors to help with the power delivery and they said that this is merely “a myth”.

Does anyone know of a solution to this problem? Your suggestions will be greatly appreciated.

[J.T]

i have been informed by Lexus Derby that they are aware of this and there is a remap due soon which should imrove the terrible turbo lag and improve power delivery.

[Steve ( West Mids )]

Have you asked to drive a courtesy car / demo as a comparison? This would rule out or confirm something specific on your car.

[Matus]

Jonnyboy> How many miles has your car?

Example: I have found this unfortunate trait rather dangerous, especially when attempting to join a busy road or roundabout. If the revs to drop below 2,000RPM, the engine immediately bogs down leaving you having to frantically slip the clutch in order to build the revs back up to a level where the engine actually relinquishes some power. As well as being dangerous, this is not very dignified and cannot be much good for the clutch either.

I think this is because your car is new...Mine was the same but now at 14.000kms (~9.000miles) the car accelerates on second and third from 1.600rpm

Being an experienced driver and having owned and driven numerous 6-speed turbo diesels, I would say that the 1st gear ratio is simply too high for the job.

this car has a bit different gearbox rations, so it needs different approach

I think that the first gear is just okay, just don't be afraid and floor it when you need the acceleration. Floor it, wait till the engine gets in revs and release the clutch and the car is very quick even from standstill.

Another example: Try driving at exactly 30MPH on the flat then depressing the accelerator to the floor when you reach a derestricted section of road. With my car it takes a full 3 seconds before ANY change in acceleration is felt. What with the power only being delivered from 2,000PRM onwards, when driving in 3rd gear at 30MPH the engine is just below this critical speed ensuring this numb and rather frustrating response on attempting to accelerate.

This is matter of new car, third accelarates from 1600rpm

Having also experienced problems with the useless 6th gear (see my previous post), I can only deduce that, when Lexus changed the final drive in an effort to make a distinction between the “Sport” model and the rest of the range, they have upset the gear ratios to the point that they are now not really practical for the job.

As I read through forum and look on england speed limits with conclusion that sixth is useless, but what I don't understand, why are you worried about that... less gears means less gearchanges and this means less work with the clutch etc = more comfort. I find this cool. 5 gear ratios are enough.

I can honestly say that I have never driven a turbo diesel which such strange and un-diesel like power delivery.

why did you buy it then?

I like this car and I like also because of the un-diesel like power delivery. Normally diesel gears are way too short, second pulls 40mph, third 60-65mph etc... This car goes on second gear 60mph and fourth gear is usable from 38mph till 100mph. This range is common in petrol cars, not in diesels.

When you have bought the car already, try to find the pros in long gearing, not the cons...

[Matus]

The only negative thing, which I see on 220d engine, is the turbo lag. BMW and Honda sorted this out, toyota hasn't.

[jonnyboy]

I am due to take the car to Lexus tomorrow so that they can attempt to fix the following issues (again):

- Very poor fuel economy.

- Rough idle when engine is cold (accentuated when outside temperature is also cold).

- Overrun when gently backing off the accelerator, e.g. when driving in slow moving traffic.

- Awful turbo lag.

- All four windows lowering themselves to the bottom, always when the car is locked (therefore invalidating my insurance).

- Intermittent central locking i.e. not locking and sometimes not unlocking.

- Passenger windscreen wiper only touching on the very outer edges when outside temperature is around or below freezing (wiper heater is working OK - Lexus checked). In wintry weather this results in the passenger side of the screen becoming completely opaque, therefore restricting the driver's view.

Combine all this with a gear box full of ratios which makes no sense at all and you have a car which is pretty sub-standard in my estimation. I lease my car so only have to put up with it for another year and a half. I pity those of you who have actually shelled out your hard earned cash as the residuals will probably be very poor if these rather fundamental issues remain unresolved.

Nobody's perfect. I don't mind if Lexus have made a mistake as long as they hold up their hands to it and promptly do their very best to find a solution. What I don't like is being fobbed off by the dealer and Lexus GB, both of whom have made out as though the car's shortcomings are somehow my fault!

e.g. When replying to my comments about the 6th gear which cannot be used legally in the UK Lexus said,

“With regards to your concerns about the 6th gear on your IS220d, I can confirm that the model was designed and manufactured for the European market with performance and reduced emissions in mind. We would not expect 6th gear to be used at speeds below 75MPH and as such the 6th gear is in effect intended for use on the main European routes such as the Autobahns”.

They might as well have said,

“Well it’s your own fault for living in the UK”.

This lady seems to have overlooked the fact that there was absolutely no mention in their UK marketing brochure of being unable use the 6th gear legally in the UK. Are any LOC members in the legal trade? If so, perhaps you could shed some light on the legalities of this. Any comments will be grateful appreciated.

Have you asked to drive a courtesy car / demo as a comparison? This would rule out or confirm something specific on your car.

I will be getting a courtesy car but these are always petrol rather than diesel.

[Steve ( West Mids )]

ask for a diesel

[Northern Boys Luv Gravy]

I've had a number of diesel cars and on none of them did the turbo kick in below 1800-2000 rpms, giving a narrow power band of between 2000 and 4000 rpms. I've only driven the 220d as a courtesy car but it appeared no different to any other marque I've had. The fuel economy seemed a bit worse than our Audi 2.0TDI (but I would expect that as it has 30 or so more bhp and an extra level of emissions kit) and it was a bit smoother - but then again they are both diesels and sound tractor-like at idle.

The windows down bit is a puzzler - we had a similar thing happen at a place I worked once - the windows of our VWs and Audis in the carpark kept winding down by themselves. We never did get to the bottom of it.

[Scarlet Pimpernell]

The windows down bit is a puzzler - we had a similar thing happen at a place I worked once - the windows of our VWs and Audis in the carpark kept winding down by themselves. We never did get to the bottom of it.

"Phantom of the Opener"

Anyway, I do agree the lag is a bit sharp, and as I've said before the Journo's weren't totally wrong!The problems is that 177bhp hits too soon and too hard in a narrow band, accentuating the feeling of lag lower down.

The Audi 2.0TDi is better in this regard...as is the Beemer!!

[jonnyboy]

I've had a number of diesel cars and on none of them did the turbo kick in below 1800-2000 rpms, giving a narrow power band of between 2000 and 4000 rpms.

Fair comment; however, what with the higher geared final drive on all but the sport model, the gear ratios do not translate very well to the road speed, leaving the engine struggling, ensuring that fast starts have to be accomplished with clutch slip.

My last TD was a Mondeo ST TDCi 2.2, a car that I considered to be very versatile and a rather good drivers' car. Excellent handling, plenty of power available throughout the range, picked up well from a standing start with no clutch slip, 6th gear engaged at 60mph and pulls like a train all the way to 140mph (where permitted!), enough space to whisk the family off the beach at the weekend, all this and a frugal 45mpg too (despite my having chipped it up to 185BHP with a Bluefin).

Having owned and driven Audi, BMW, Ford & Vauxhall TDs and with the 6-speed turbo diesel now being a well established line and a highly regarded choice for most, I am at a loss as to how Lexus could make such a monumental ball-up of something as fundamental as the gear ratios.

It seems to me that Lexus were perhaps trying too hard to set the IS220d "Sport" apart from the other models in the range. On that note, can anyone verify whether or not the sport suffers from these issues i.e. Clutch slip for a fast standing start, poor acceleration from 30mph in 3rd, unable to engage 6th below 75mph?

[Scarlet Pimpernell]

It seems to me that Lexus were perhaps trying too hard to set the IS220d "Sport" apart from the other models in the range. On that note, can anyone verify whether or not the sport suffers from these issues i.e. Clutch slip for a fast standing start, poor acceleration from 30mph in 3rd, unable to engage 6th below 75mph?

The Sport from memory is a tad sharper at take-off - however it's really noticeable as an improvement over the non-Sport only when you get to 25-30mph - 2nd-3rd-4th gear and beyond - it's lighter and fleeter.

The Sport will sit comfortably at 60-65 in 6th, whereas the non-Sport is uncomfortable at 70 in 6th in some conditions, and doesn't pull too cleanly unless the road is flat or down hill.

I liken it to a road racing bike compared to a mountain bike. In this analogy, the Road bike is the non-Sport model that you and I have - it's more effort in a like for like gear.

I've now got to the stage where I don't attempt any racing starts at the lights - most cars will beat me. It worries me what the clutch is doing when I slip it and so I end up revving to 2500/3000rpm when I need a quick start at a round about!!

I reckon you need to drive one for a period of time. I reckon it's what the 220d should have been, but then it would have too many Carbon for the company car drivers.

They've tried to make the SE the most economical/cleanest and the fastest, but I'll leave it to you to decide whether you think it's worked!!

I've had a number of diesel cars and on none of them did the turbo kick in below 1800-2000 rpms, giving a narrow power band of between 2000 and 4000 rpms.

Absolutely true - however with the tall gearing in the 220d, it becomes hard work sometimes. You're constantly changing gears when taking corners or slowing down - something I seldom did in my Audi which semed to pull in any gear almost at any speed...

I know the Lexus is more powerfull, and I also know that Eu5 may be the killer here, but an Auto would have fixed all of this!!!!!!!!