Are There Any Universal Issues With Acceleration Hesitation With The E

[bostonsnowboarder]

I see that there are a couple of transmission related TSIBs due to flare. How many cars are affected by this? is it all of them?

Are there any major hesitation issues to look out for with the ES350 - like with the 02-06 ES330's or is that issue taken care of?

I have been thinking about getting a pre-owned 04 or 05 ES330, but now after having test-driven a few cars, and reading the threads on this forum, I am beginning to think that I should spend more and get an 07 or 08 ES350. Have there been any universal issues, like the hesitation issues with the 330?

An aside off-topic question - do previous owners of ES300 or 330s find the seat comfort of the 350 to be as good or better than the older models?

thanks

[SW03ES]

Alan (amf1932) had an 03 and was particularly bothered by the transmission hesitation ad upgraded to an 07 and is happy with it. The 07s and 08s have some other issues including a transmission flare between a couple gears, you can read more of it there.

The "transmission hesitation" has never bothered me. Have you been bothered by it in the older models you've driven?

For me the ES350 is a mixed bag vs the 02-06 ES. I like the new exterior, I like the new features, power, and the way it drives. I do however believe that the interior of the car is several steps down from the interior of the 02-06. Its enough of an issue for me that I won't be replacing my 03 with an ES350.

If you're looking at spending the money on a new or almost new ES350 and you don't have an aversion to buying used I might suggest you look at an 04-06 LS430 for about the same cost.

As for seat comfort, I've driven ES350s extensively both test driving and as loaners, I think the seat comfort is about the same.

[bostonsnowboarder]

Alan (amf1932) had an 03 and was particularly bothered by the transmission hesitation ad upgraded to an 07 and is happy with it. The 07s and 08s have some other issues including a transmission flare between a couple gears, you can read more of it there.

The "transmission hesitation" has never bothered me. Have you been bothered by it in the older models you've driven?

For me the ES350 is a mixed bag vs the 02-06 ES. I like the new exterior, I like the new features, power, and the way it drives. I do however believe that the interior of the car is several steps down from the interior of the 02-06. Its enough of an issue for me that I won't be replacing my 03 with an ES350.

If you're looking at spending the money on a new or almost new ES350 and you don't have an aversion to buying used I might suggest you look at an 04-06 LS430 for about the same cost.

As for seat comfort, I've driven ES350s extensively both test driving and as loaners, I think the seat comfort is about the same.

I have test driven about 7 different 04 and 05 ES330's, and what I cant understand is that there is quite a bit of variability from car to car. ON some of them, I could easily and on purpose demonstrate the hesitation after slowing down and then trying to re-accelerate, but on others it did not happen. Maybe it does not happen all of the time? I have read the thread on the 02-06 ES forum (took a couple of hours to read all the way through) and I still cant explain why there is so much variability.

Going from a used 05 ES330 to a slightly used 07ES350 seems like about a $7000 jump, and going to a new one would be much more I am sure - not sure if I want to go that high. I guess the best bet might be to carefully do a long test drive on an ES330 and buy one that has the least amount of hesitation. Other than this issue, I love everything else about the car.

[SW03ES]

The transmission is also adaptable and the hesitation seems worse depending on what driving style its adapted to. You can disconnect the batter for 10 minutes or so to let it reset.

[AZ08LexusES]

I have an 08 which I love to drive. It has a very small hesitation, but I attribute it to automatic transmissions in general. When you slow down, it doesn't necessarily downshift, so when you re-accelerate it has to figure out what gear it needs to be in to respond to the sudden change in acceleration. My last car was an 00 Honda Accord Coupe with manual transmission, while my wife's was a '99 Honda Accord EX with automatic transmission, and the difference was huge. When I do not want the ES to hesitate, I switch it to manual, put it in the gear I want, and wooosh! It goes!!!

Now, extra hesitation may be caused also by fuel system issues. Depending on the quality of the gas being used (not octane necessarily) over time, fuel filters, fuel injectors, and gas lines may get clogged. This will cause a fuel defficiency condition, and the car will hesitate. It may not be what you are running into, but you know...

[bostonsnowboarder]

The transmission is also adaptable and the hesitation seems worse depending on what driving style its adapted to. You can disconnect the batter for 10 minutes or so to let it reset.

Do you think that the difference in hesitation that I found from one car to another (within the 05 series) is solely due to how it has "learned" from its previous owner, or are there other inherent differences? in other words, what I am trying to figure out is if I shoudl be put off by an unusual amount of hesitation in a particular one that I may buy, or can it all be "reset" to the same "baseline" level of hesitation by unplugging the battery.?

[SW03ES]

I honestly don't think there would be that much variation among the model set. One way to make sure would be to disconnect the battery on one of the cars you feel has the lag and see if it helps.

[bostonsnowboarder]

I honestly don't think there would be that much variation among the model set. One way to make sure would be to disconnect the battery on one of the cars you feel has the lag and see if it helps.

It could be I suppose because of the way I drove on the particular test drive, or even my imagination, but it really did seem that there was noticeable difference from one 2005 ES to another. Your idea is good - if the dealer will let me, I'll go back and on one of the one's with more lag can try to disconnect the battery. ALso - I'll look inside the hood to see if one or the other models has had the latest flash upgrade. THere are 3 05's at one particular dealership that I am considering.

[bostonsnowboarder]

I honestly don't think there would be that much variation among the model set. One way to make sure would be to disconnect the battery on one of the cars you feel has the lag and see if it helps.

my dilemma is that I saw a 2005 with nice low miles (22,000) at another dealership at a reasonable price, but I thought that it had more lag than other cars I have seen, so that put me off it. I suppose I could go back and ask them to let me do the battery unplug and then re-drive it. I am sure that the salesman are well aware of the hesitation thing even though they never say a word about it.

[SW03ES]

Thats what I would do.

And don't bet that the salesman will be aware of the issue. On these forums it seems like everyone knows about it. I however have never encountered an 02-06 ES owner in person that has the issue.

[wwest]

There is a NCF, New Car Feature, for the '08 Avalon which may be used to address the 1-2 second downshift delay/hesitation symptom throughout the Toyota/Lexus fleet.

Basically the idea is for the engine/transaxle ECU to closely "watch" the rate at which the gas pedal is released and provide the "correct" transaxle shift shedule/pattern accordingly. A slow release of the gas pedal will result in an upshift as would be normal for a driver wanting to enter cruise mode from a period of acceleration. On the other hand a quick/sharp release of the gas pedal might/would indicate a wish to use engine braking to slow the car to a lower speed.

The problem arises in defining "slow" vs "quick" for each and every individual driver. Now, I am of the FIRM belief that any driver "learned" technique or style is erased, completely, when one turns the ignition key off. Any driver unique charactoristics MUST start from scratch each time/cycle of an engine restart IMMHO.

I have read, years ago, an engineering white paper that indicated that within a very few seconds of starting the car in motion the driver style technique is refined into one of four types. Within another longer period it is more finely refined into 1 or 16 style/types. Thereafter it keeps a 120 second running record (anything beyond 120 seconds is lost/erased) and continuously refines the driver style/type according to current technique.

So, now, if the 1-2 second downshift delay/hesitation is to be a function of the rate at which the driver eases off the gas pedal, or not, then obviously the system must have had the time to "learn" the driver's style/technique in this regard.

That just might explain the randomness of test driving different cars in this regard.

The base problem..

If you are accelerating slightly, say in an acceleration lane upon entry into a freeway lane, and lift the gas pedal in order to slow enough to match that upcoming opening in traffic, the transaxle may or may not upshift in response to your actions. If it does happen to upshift then obviously it will not be in the correct gear ratio if you now want to quickly return to the same, or greater level of acceleration. And if it did upshift all of the reserve ATF pressure has been exhausted and there is none left for the downshift you have just "requested".

As a result the DBW, e-throttle system, will delay the onset, rise, of engine torque in response to the newly depressed gas pedal position until enough ATF pressure can be attained to provide the pressure/flow to accomodate the newly required transaxle downshift.

[bostonsnowboarder]

Thats what I would do.

And don't bet that the salesman will be aware of the issue. On these forums it seems like everyone knows about it. I however have never encountered an 02-06 ES owner in person that has the issue.

I test drove a different ES and despite deliberately and repeatedly trying to reproduce the hesitation that has been reported in the forums on these cars, could not reproduce any hesitation at all. So, I have bought this car, since the other one that I was considering did appear, at least on my particular test drive, to have repeated hesitation. How much of this is based on previous learnings vs unique aspects of each car I dont know.

Now, for the car which I have just bougtht, I would leave to keep things just as they are, however, under the precertified program they will be replacing the battery. So, I will be getting the car delivered to me with any previous learning reset. So, I'll report back on what happens. I hope that, on learning my particular driving habits, it does not then create new hesitation!

Boston Snowboarder

[Just bought an 05 ES330 Silver/Blk w/ 17 inch alloys/rain sensing wipers/hi intensity xenons]

[bostonsnowboarder]

Thats what I would do.

And don't bet that the salesman will be aware of the issue. On these forums it seems like everyone knows about it. I however have never encountered an 02-06 ES owner in person that has the issue.

I test drove a different ES and despite deliberately and repeatedly trying to reproduce the hesitation that has been reported in the forums on these cars, could not reproduce any hesitation at all. So, I have bought this car, since the other one that I was considering did appear, at least on my particular test drive, to have repeated hesitation. How much of this is based on previous learnings vs unique aspects of each car I dont know.

Now, for the car which I have just bougtht, I would leave to keep things just as they are, however, under the precertified program they will be replacing the battery. So, I will be getting the car delivered to me with any previous learning reset. So, I'll report back on what happens. I hope that, on learning my particular driving habits, it does not then create new hesitation!

Boston Snowboarder

[Just bought an 05 ES330 Silver/Blk w/ 17 inch alloys/rain sensing wipers/hi intensity xenons]

oh, I should add that I checked under the hood and it appears to have NOT had the TC004-03 enhancement, which I will not have done, unless there are any new hesitations that develop (I am praying for things to stay just how they are now!)

[SW03ES]

Congrats!

Yeah, if you're happy with it don't have the ECM reflashed.

[bostonsnowboarder]

I have read, years ago, an engineering white paper that indicated that within a very few seconds of starting the car in motion the driver style technique is refined into one of four types. Within another longer period it is more finely refined into 1 or 16 style/types. Thereafter it keeps a 120 second running record (anything beyond 120 seconds is lost/erased) and continuously refines the driver style/type according to current technique.

So, now, if the 1-2 second downshift delay/hesitation is to be a function of the rate at which the driver eases off the gas pedal, or not, then obviously the system must have had the time to "learn" the driver's style/technique in this regard.

That just might explain the randomness of test driving different cars in this regard.

About the white paper that you refer to, is that whilte paper with regards to the 08 Avalon or the older Lexuses? If it applied to the Lexuses, it would'nt really make sense to me, as that would me that it is essentially re-learning a new pattern of driving every 120 seconds, so you might have hesitation one moment but yet no hesitation 2 minutes later. THat is not the pattern that people seemed to have described on the forums for those cars that do hesitate.

As for the car that I bought, I gave it a good 30 minute test drive with no apparent changes in performance at any time.

A further question about this whole issue - while I may not understand the full mechanical implications of the hesitation, but - if a car did have significant enough points of hesitation or poor shifting to result in little "clunks", would'nt those "clunks" eventually over time lead to premature wearing of the transmission parts? Has anyone with an 03-06 Es with high mileage had premature transmission failures?

[wwest]

I have read, years ago, an engineering white paper that indicated that within a very few seconds of starting the car in motion the driver style technique is refined into one of four types. Within another longer period it is more finely refined into 1 or 16 style/types. Thereafter it keeps a 120 second running record (anything beyond 120 seconds is lost/erased) and continuously refines the driver style/type according to current technique.

So, now, if the 1-2 second downshift delay/hesitation is to be a function of the rate at which the driver eases off the gas pedal, or not, then obviously the system must have had the time to "learn" the driver's style/technique in this regard.

That just might explain the randomness of test driving different cars in this regard.

About the white paper that you refer to, is that whilte paper with regards to the 08 Avalon or the older Lexuses? If it applied to the Lexuses, it would'nt really make sense to me, as that would me that it is essentially re-learning a new pattern of driving every 120 seconds, so you might have hesitation one moment but yet no hesitation 2 minutes later. THat is not the pattern that people seemed to have described on the forums for those cars that do hesitate.

As for the car that I bought, I gave it a good 30 minute test drive with no apparent changes in performance at any time.

A further question about this whole issue - while I may not understand the full mechanical implications of the hesitation, but - if a car did have significant enough points of hesitation or poor shifting to result in little "clunks", would'nt those "clunks" eventually over time lead to premature wearing of the transmission parts? Has anyone with an 03-06 Es with high mileage had premature transmission failures?

"every 120 seconds.."

Think of it this way...You pull out of your garage early in the morning and drive through YOUR neighborhood, lets say about 2-3 miles through YOUR neighborhood, slowly, sedately and quietly,......then you get to the freeway ramp and become a formula ONE driver.

And it's a "running record", everything, all information, as it reaches 120 seconds of "age" rolls off into never/never land but the ECU ALWAYS has the most current 120 seconds of driving to rely on, "learn" from.

And no, the while paper, as I said, is something I remember reading on the internet many years ago now. But the primary point is that the driver style/technique "learning" software must NOT be biased by some previous driver of the vehicle, and if correctly designed will adapt to driving style/technique as/if the driver changes.

And yes, absent the adoption of DBW, E-throttle in the fleet to "protect the drive train", we would likely still be seeing RXes with premature transaxle failures as happened for the '99-'00 series, or ATF that is severely burned as is happening with the '01-'03 RX series.

[SW03ES]

Has anyone with an 03-06 Es with high mileage had premature transmission failures?

I've never heard of a case where someone has. Mine has over 100k and I've never had any problems.

[wwest]

ab-o-li-tion

1. The act of doing away with or the state of being done away with; annulment.

2. Abolishment of slavery.

Following statement taken from Lexus NCF, New Car Features, for the '99 RX300.

1. Direct Clutch Fluid Pressure Control

Direct fluid pressure control using linear solenoids is adopted for fluid pressure control of B1 and C2 for

engagement/release upon shifting between the first and second speeds and between the second and third speeds.

The output pressures from linear solenoids SL1 and SL2 are led to B1 and C2 control valves for optimum

control of each clutch pressure. As a result, the automatic transmission size is reduced by accumulator abolition and fine fluid pressure control not possible with clutch fluid pressure control using accumulators.

"..the automatic transmission size is reduced by accumulator abolition..."

Fluid pressure accumulators are often used to sustain/maintain fluid pressures for the brief periods it takes for the hydraulic pump speed to rise to the required flow level.

Eliminating the accumulator was undoubtedly one of the methods used to make room for fitting more robust components into an otherwise light duty Camry transaxle that was now to be used to haul around a much bigger and heavier vehicle.

Premature transaxle failures for '99 & '00 RX300's.....

Prematurely burned ATF fluid for the '01 to '03 RX300 series...

1-2 second downshift delay/hesitation throughout the Toyota/Lexus FWD and F/AWD fleet due to DBW being used to delay the onset of engine torque until the gear type ATF pump could pump enough fluid with the engine at idle to bring the pressure back up to snuff....

Engine flare during 3-4 upshifts...

All traceable to one simple engineering mistake made during the design phase for the RX300.

[BaddBoi70]

The transmission is also adaptable and the hesitation seems worse depending on what driving style its adapted to. You can disconnect the batter for 10 minutes or so to let it reset.

Steve,

Thanks for the tip, I was unaware of the adaptive driving memory.

[wwest]

The transmission is also adaptable and the hesitation seems worse depending on what driving style its adapted to. You can disconnect the batter for 10 minutes or so to let it reset.

Steve,

Thanks for the tip, I was unaware of the adaptive driving memory.

Confusion STILL reigns surpreme...!!

Modern day cars do have adaptive "learning".

But of two separate types.

From the time it leaves the factory it continuously learns and adapts to variances in the sensors and servo devices. Some of those are kept in non-volatile memory and can only be erased via a factory technician. Some others are in volatile memory and can be erased by disconnecting the battery or pulling a specific fuse temporarily.

As a for instance my '93 Ford Ranger, 140,000 miles, has an idle air bypass valve, basically a simple electrical bang/bang, on/off, solenoid but through the use of PWM, Pulse Width Modulation, of the applied voltage it becomes a LINEAR servomotor. Every time my PU cames up for the emissions test I have to remember to clean the idle air bypass port, disconnect the battery so the ECU forgets the previous PWM parameter, and then give the ECU time to learn the new parameters by going through several drive cycles before going for the emissions test.

Most modern day automatic transmissions have as many as 4 of those "simple" solenoids used as linear servomotors via the same "learning" process.

So when you disconnect your battery, yes, YES, the car will drive differently for the next few drive cycles.

BUT NOT BECAUSE YOU HAVE ERASED THE DRIVER'S DRIVER STYLE/TYPE HISTORY.......!!

Driver style/type history is ERASED each and every time you start the car in motion and many of the driver style/type parameters are updated as you drive.

Could it be any other way and still be acceptable to the driving public...??

How many divorces would result if it were not so..??