hylyner, I am not a "biased individual". I have it at a guess that I have owned more Toyota products than you (more than 10, I lose count) and am very familiar with the company and have enjoyed their products in the past. My statements are based on FACT, and when a problem exists I state it so. Furthermore my profession involves software controlled logics and robotics and while I am no expert on Toyota transmission firmware, I can recognize a logic-control problem when I see one.
Two questions for you: 1. Have you driven a new Maxima? 2. Have you driven a new Accord? I guess not because if you had, you would have been silent. If you don't have the problem then breathe a sigh of relief and realize that you have no factual grounds for comment, however to insinuate that others who have a problem are biased or have some other affliction only serves to demonstrate ignorance.
I have to agree with hylyner here on the topic. I have found no problem with the tranny in my Avalon Limited after 5 months of driving. The throttle is very responsive when I'm in an aggressive mood, but amazingly gentle in stop and go traffic.
I have driven both a Maxima and an Accord, and for the record, I've driven an Acura TSX and an TL. Although the Maxima is somewhat more responsive than the Avalon, I suspect that they are simply programming the computer in such a way as to please their target demographics. The TSX and TL perform similarly as the Avalon, and my friend, who is a car enthusiast and a proud owner of a well-maintained TSX, has confirmed that Honda is well-known for their automatic tranny problems, both hardware and computer.
I see no reason to get personal here. People simply notice different things. I have sharp ears, and I probably notice a lot more of the quiet rattles than most of you (being at the age of 23 probably helped). What the Toyota tranny is exhibiting may be by design. Some may argue that it's bad design, but there is the silent majority who think it's working just fine. My dad spent 1000 miles in my Avalon and he loved just how responsive it is compared to his 2001 XLS.
Thanks for the supportive comments Fragmire. I've driven both the Maxima (extensively) and Accord (occasionally). Both are very nice drives. I'll keep the Avalon though.(Our third Av, and and a number of other Toyotas since the 70s.) You're right. To each his own.
Does the Avalon have a transmission problem or not?
People and dealers appear to making excuses for a transmission or throttle problem. It's not uncommon for dealer to tell false truths to the public about problems. In many cases they refuse to admit that there is a problem.
Does the transmission really hesitate because it’s a learned behavior? Perhaps it needs Prozac in the oil.
Is the alleged problem with the transmission similar to the Lexus transmission issue? I refrained from buying an ES 330 a few years back b/c of the tranny problem and now I find myself doing the same thing on the Avalon .it’s a real shame b/c it's a nice looking car.
The best answer anyone could can suggest to you is this: Some here will insist there is a problem, others will say no there isn't. Some will report experiencing it, others will say it hasn't happened to them. If human nature holds true, it's likely negatives outnumber positives in these forums because people tend to be more vocal about bad rather than good. Truth be told, we haven't heard from the million or so who don't participate in these forums. The very small percentage of yays or nays heard from in these forums is really no valid indication one way or the other. The closest thing to any form of broad based opinion would be the many positive consumer surveys out there, PLUS the fact that Toyota in general is doing well in the market place. It's probably safe to say the Consumer wouldn't continue to buy anyone's product in such overwhelming numbers if it wasn't good. As regards your question: "What happened to Japanese Quality?", It could be said that their quality hasn't changed, but the Big Three automakers have learned to do quality better. In other words, the playing field is much more level now than a few years ago. I for one, am glad to see that. Now, if GM, Chrysler, and Ford can only get their fiscal ships in order......!
My 2006 Avalon is growing icicles in the odometer display and is camouflaging the fourth figure in my mileage reading. I bought the car this October and I am not happy about this at all. They are going to have to replace it, however, does anyone know the effects of such a repair and how it will affect the aesthetics of my dashboard area? Please inform.
I am Ole Geaser and usually accelerate gradually from a stop position (I'm not a lead foot). My Avalon has 5000-miles and the transmission still cannot decide what gear it likes, it switches gears back and forth until I reach 35 to 45 MPH. I guess this would be called 'gear' hunting. I wonder how Lexus corrected this problem on the E-300?
>The very small percentage of yays or nays heard from in these forums is really no valid indication one way or the other.
The sample of car owners in this forum is a cross-section of all the cars sold. The people writing here received cars randomly. So this is a sample of the car.
Quote: "The sample of car owners in this forum is a cross-section of all the cars sold". Unquote. Well my friend,, if you truly believe that, then perhaps we should sit down and talk about the bridge I have for sale!!
You are dead wrong. You CANNOT judge a car's reliability by what people posts on the internet forum. This is a very very unscientific method to determine whether a car is problematic or not. Some people specifically have a grudge against a particular manufacturer because for some reason the car didn't satisfy their needs. That certainly doesnt mean the car is defective
You may believe what you want, but I follow several discussions and there is a connection between what shows up here vs what the real world experiences with the car. Call it convenience sampling or cluster sampling. It's just as good a CR's method!
Go through the old Accord Prob & Solutions. Look at the 03 comments as people bought those and then note what things got changed midyear and for the 04 model...
Motown is correct. These forums, as informative and helpful as they are, cannot be assumed to be indicative of the real world. They are not statistically representative of what is really happening in the automotive marketplace. As an example, take the M&R forum called "Engine Hesitation-All Makes and Models". Nine out of ten posts that forum are by the same 7 or 8 people. All these few individuals talk about is one manufacturer. If one didn't know it was always the same group discussing an issue with that manufacturer,it would be easy to assume the issue was only about a problem with that single manufacturer. But it's not the case. It's a few individuals using that topic to discuss one issue. Another reason why one cannot assume these forums are reality has to do with what I would call "pseudo posts". It is quite simple for one person to appear in these forums with any number of different usernames. One person using that technique can make it look like many people talking about one single problem; basically manipulating the system for whatever reason. It happens, and I suggest more than enough in spite of Edmund's wishes that it didn't. So for these and many other reasons it wouldn't be adviseable to assume these forums are anywhere near what the general public thinks or what may really be the case from a consumer viewpoint. That said, they are often interesting and informative, but absolutely by no means a statistically representative sample of overall consumer opinion. Assuming anything otherwise would be extremely unwise, if not downright foolish.
imidazo- also disagree - would suggest to you that anybody who even takes the time to read thru these forums and/or participate in it are, by definition, car nuts and likely very discerning about their cars. Add to this the Avalon demographic - generally older, more affluent, likely capable of buying whatever car strikes our fancy - and what you have is a bunch of us that know what we want and used to getting it. It doesn't surprise me at at all that a number of the comments you see on this (and other forums for cars of this type) tend to be negative or, for that matter, there are a few posters that seem only to have some sort of axe to grind. But, positive or negative, hardly a crossection of Avalon owners or even car buyers, in general.
Those of us in states with no state income tax are hit with huge property taxes. In Houston, we pay about 3 1/8% in property tax. They'll :mad: get you one way or another!!
I am wondering if anyone has experienced a problem with their paint on their Avalon? I just noticed that there are 6 or 7 spots of discoloration under the clearcoat. These are located above the passenger side doors, along the strip that is just below the roof of the car. They almost look like small irregular pieces of tape on the paint, and then they were clearcoated over. Not a color so much as darker spots. Some the size of a pea, others more elongated, about 1/8" wide and 1/2" long. The car has about 900 miles and I never notice them until a few days ago. I am sure they were not there before. You can't clean them off, and they are not dirt, smudges, etc. Anyone have any ideas?
I have my big white whale with over 10th miles on it & like all my previous toyotas have NOT had ANY problems at all with it. Most of the posts I read seem to be minor. Still happier than a pig in swill on a hot summer day!
I hope this will make you feel better. We pay a 7% federal tax plus an additional provincial tax (8% in most provinces) on almost everything we purchase. That's 15% added to most goods and services purchased. Although not perfect, it does include free health care (doctor's appointments, heart surgery, cancer treatments, etc.).
I happened by the local Buick dealer last night after closing and found a new Lucerne on the lot -- and unlocked -- so I had a chance to sit in it.
It is a very pretty car but I wanted to mention that for tall drivers (I'm 6'3") visibility is poor. The windshield cuts much too low for me and would require leaning over the steering wheel & dash to see stoplights.
I'm sure it's fine for normal sized folks but wanted to pass along this tidbit of info since most of us haven't had a chance to see the Lucerne yet.
Let's see. This forum is for those who [1] know how to use the Internet, [2] own a 2005/2006 Avalon, and [3] have the time to read and post messages. Let's also not forget a very important point brought up by hylyner: people who have something to complain are usually the one talking. I'm very confident that there are many happy Avalon owners out there who are simply not posting here.
Now let's compare it with the CR method. They take random sample of 2005/2006 Avalon owners regardless of the 3 conditions above. So how is forum a good a review as the CR method?
Not much point in trying to convince anyone who refuses to accept reality. There will always be those who won't acknowledge facts, even when there's no rational argument to suggest these forums are a valid cross section of the car buying public. One can only speculate on motive for even suggesting it. (Perhaps the term "problem car" could be a clue--is it intended that readers believe it ?) Take some consolation in knowing there are indeed, a vast majority of Av owners out there who are completely satisfied with their rides. Even in this forum, as statistically invalid as it is, the positives far outnumber the negatives.
i agree with all you have stated....once you start to travel down that slippery slope of "technology intervention" you're opening up a real can of worms. the only point i would make in defense of "progress' is that they (the engineers and designers) don't always get it right the first time. remember, the drive by wire (for emmissions) is new stuff...it's only a few years old on main stream cars. abs is an example...early versions of it were not the most reliable system...it took time before it was perfected.
personally, i would prefer cars with less complexity but this is just a dream: between state,local and federal requirments and the big selling point in the general public for all the gadgets and do-dads, a simpler car with less electronics is just that: a dream.
there are volatile and non-volatile memories for computer systems...the algorhythim for "smart" transmissions does infact keep the driving patterns of the driver for a period of time...is it longer than 3 minutes? absolutely...how long does it "remember"? you would have to consult with the programmer to determine that fact. any volatile memory will be lost when the power is switched off...the learning feature is not volatile.
At this point I don't see how anyone can question whether or not the Toyota and Lexus 5-speed transaxle has a firmware flaw within the engine/transaxle ECU. Such flaw only exhibiting itself under certain unique circumstances. Some of those circumstances are clearly driver action (inadvertent) related but the base flaw lies at Toyota's feet.
It is begining to look as if the problem relates to an attempt to squeeze the highest possible mileage out of the fuel.
All of the vehicles involved seem to have been upgraded to a newly developed wide bandwidth more sensitive non-resonant knock/ping sensor. My guess is that this allows the engine, during cruise, to be operated beyond the standard A/F mixture ratio, 14.7:1, well into the area of leaner mixtures.
Prior to this development the downstream oxygen sensor was the sole feedback source for controlling the mixture ratio, and it would not work either above 14.7:1, or below. Under acceleration or high engine torque the ECU uses the MAF/IAT sensors in order to run the mixture RICH.
With the advent of the new more sensitive knock/ping sensor the mixture can be deterministically "tuned", leaned, in realtime, using the knock/ping sensor to be sure the engine isn't damaged via even the slightest knocking/ping.
So now the engine/transaxle ECU has a "map", detailing the A/F "leaning" level each individual cyclinder can withstand before knocking. Due to the inadvertent uniqueness of each individual engine this map is "learned" after the vehicle leaves the factory, and is likley, of obvious necessaty, continually relearned as you drive.
I now have ~20,000 miles on my manual 6-speed 2001 Porsche C4. Over time "my" ECU has learned just what gear I need to shift down into when I wish to accelerate, slowly or quickly, rapidly, from my current speed to a higher one.
Your Toyota/Lexus engine/transaxle ECU, by factory design, "wants" to be in the highest gear appropreate at any given time based on roadspeed and throttle position.
Remember it's a five speed gearbox, and when you go from closed throttle where is may very likely be in, have shifted into O/D, to open throttle, the ECU must quickly decide "your" intent, all without knowing what's in your mind or seeing the road ahead.
Slowly open the throttle, or open the throttle quickly but to a mid-position and it will always default to the hihest gear that would yeild the best MPG. But now you sense a lack of response to your throttle input and push the gas pedal farther down. Oops, the ECU now wants to put you into third instead of the previously commanded downshift into forth. But now it must want for the downshift into 4th to be complete before commading another downshift.
At this point things within the transaxle may be getting a bit dicey. During the previous coastdown period the engine RPM was dropped to idle so the transaxle's hydraulic fluid pressure pump isn't moving very much fluid. Besides which durimg coastdown the transaxle's line pressure is dropped to an absolute minimum by the ECU inputs to the control solenoid.
So, the initial downshift into 4th may have exhausted the pressure reserve in the accumulator and now the next downshift must be delayed until the pressure is again bult up, with the engine still at idle.
But now guess what?
Just as the downshift into third begins you push the gas pedal to the floor. Oops, again, says the ECU, now I need to be in second....
Clues:
The dealers have told some owners who are experiencing the engine hesiation problem to switch to premium fuel and at least a few of those owners have indicated that helps.
Now that winter, cold weather, is upon most of us some owners are saying the problem is somewhat lessened. Cold weather, denser air, more fuel, less likely to knock.
One owner had the MAF/IAT module changed out and that seemingly cured the problem.
It appears that rapid and quick gas pedal application alleviates the symptoms.
it's only a problem if it interferes with your driving style. the thing to remember about ANY automatic transmission is that it's a compromise. for the luxury of not having to work the clutch and gear lever the tranmission does all the work...WHEN IT WANTS TO. that's why the engineers came up with "smart" trnsmissions: to try and accomodate more drivers with different driving patterns. the easiest way to override the "smart" feature is to use the transmission in the manual mode; simply put the selector in fourth. this tells the computer that you're going to shift on your own (well, to a certain degree anyway, on most cars the computer even in the manual mode will intervene under conditions that it deems hazardous to the drivetrain).
everybody drives differently: when i am approaching an intersection and i am making a left turn across oncoming traffic, i tap my brakes well before the intersection so that i don't upset the balance of the car through the turn at the intersection; this drives the people behind me crazy, since most drivers wait until they are on top of the intersection and then brake. an automatic transmission even with "intelligence" can only do so much when thre's so many variables.
The non-volatile, flash, memories are only used for program storage and factory default operational parameters, or parametric "mapping". All field learned parameters can be erased by simply disconnecting the main battery. Case in point, my idle air control bypass channel was dirty and clogged but after cleaning it I still had to disconnect the battery to get it to "relearn" to properly use the now unblocked idle air bypass.
And yes, some vehicle's may keep more that 3 minutes of driving, driving "style" memory. But how would the system react if I suddenly decided to leave my passive driving mode and became aggressive? When I "change" my driving style on the fly it needs to quickly follow my "lead", not lag behind and appear to be indecisive.
while this is beyond my understanding of transmission operation - the whole premise that this is primarily a design to squeeze an extra mpg or two makes a lot of sense with the way the car drives. Even when it is in 'S' the default gear is '4' which the tranny will hold onto even when your speed would dictate a better choice if you were to ask the car to accelerate rapidly from that lower speed. You will experience the same 'gear hunting' pheonomena starting from 'S' as you will in 'D'. I now make a special effort to exercise my Av relatively frequently and the car has not developed any bad habits. My 20 year ticketless record may be in jeopardy!
I think we have to give Wwest much credit for stating his opinions, even though he doesn't own one of the alledgedly "affected" vehicles. Wwest's theories are well presented and he obviously has a decent grasp of the technology involved. He is also one of the most active contributors to many other topics. Nevertheless, Wwest has suggested some rather serious conclusions, not the least of which in stating there is a "flaw" in the design of the DBW systems used by Toyota in these vehicles. I don't believe this is true, for a variety of reasons. All automakers today are faced with a multiplicity of challenges. First and foremost of these concerns simultanious management of three major variables, fuel economy, emission control, and driveline management of their internal combustion engines. A daunting task, considering stringent State and Federal legislation governing those parameters. It has been routinely shown the "hesitation" phenomenon being reported affects some but not others. It apparently only occurs under specific driving conditions. It varies in intensity from one owner to another--from barely noticeable to prolonged intervals in a few instances. Furthermore, it exists in other makes as well. All of these factors would tend to support that it may be design related but not necessarily a "flawed" design. Either way, it must be recognised that Wwest has put forth an opinion--his diagnosis and his alone. That doesn't mean his "flaw" concept is correct. There are many different ideas and theories on why this condition gets attention. We have to accept all of them for what they are--opinions and theories. Some day the answer to this question will be known. It should be interesting to see which of the opinions and theories set out in this forum comes closest to the truth. Meanwhile, the Avalon is a pretty good automobile. On that, almost everyone here agrees.
I would go a good deal past 'pretty good automobile' - simply the best combination of power, economy, and comfort I've ever owned. However, some examination of Toyota's motivations: What did Toyota have - a dynamically unremarkable car based on a car costing several thousand less - and while it was a fine automobile, it had nothing to really separate it (or keep up with)from the competition (Nissan/Infinit and Honda/Acura) - if it ever was to be marketed to anybody under retirement age. Well, the first thing we (Toyota)need - a really high performance engine (a first for Toyota), styling to set it apart, keep those traditional Avalon attributes of comfort and quiet, and, oh by the way, lets put it on the top the heap economy wise. You might be interested to know that the new GS300 continues with the same lower hp drivetrain because had they put the Av engine in that car there would be no reason for the GS430 upgrade - this change postponed until the 4.6 comes out. A marketing decision. Anyways, IT WORKED - the Avalons that haven't had to be ordered are moving off the lots as fast as any - at prices well above the 'norm'. Don't underestimate the power of the marketing departments - we can say the car has 280 hp and recommend premium fuel - and if, there is resistance to spending the extra 20 cents a gallon, we'll change it to run on regular at 268 hp. If we get too many complaints about electronic transmissions tuned for max economy, what then?
wwest: Thanks for the explanation. You described the problem I was having almost exactly. Since the dealer reset the system it is like driving a completely different car. No more hesitation, or "hunting" and now the upshifts and downshifts are precise and at the right time. I just hope it lasts and if not, the dealer has offered to reset it again if needed.
Trnasmission related question. For my 2002 Avalon XLS, I have started using Synthetic Transmission Fluid - Penzoil Dextron III Synthetic ATF. Does anyone have any experience/knowledge/comments about using synthetic transmission fluid? I used it in my Buick LeSabre, had 175k miles when I sold it for my Avalon. I expect over 200k miles on the Avalon. Have 90 k miles now.
About one year ago I drove my daughter's 2003 Lexus ES330 about 50 miles. It drove great,was quiet and handled the road conditions great, but the transmission hesitated 3 times, very noticeably on small inclines. My daughter did not notice the hesitations at all when she drove the car.
Before deciding on the Avalon I contacted a Lexus dealer and spoke to the sales manager about a new Lexus. I was told they would give me a great deal and wanted to see me. I asked about the hesitation in the transmission and all I got was "O" and thanked me for being interested in their cars and hung up.
Toyota has been aware of the comments and or complaints for a long time. There has been a lot of time to evaluate, confirm, redesign, and ultimalty fix it. I talked to three Toyota dealers and they all are aware of the transmission matter. What will it take to get it right? Is Toyota waiting for the majority of the Avalon owners to complain. ange1
Given the vast majority of Avalon Owners don't seem to be complaining, perhaps the suggested "wait" will be a long one? I question the idea that there may be a "problem" in a classic sense, at all. (NOTE: I'm not questioning those who say they've experienced hesitation --just that what they're experiencing may be more the way their transmission works,and it doesn't feel "right" to them) I also question the idea there's a "flaw" at the bottom of this phenomenon. People point to the TSB and say it's evidence that a "problem" or "flaw" exists. But is that a realistic statement? A TSB isn't a Recall. The entire product line isn't affected. Defective components aren't being replaced. The condition doesn't occur for everybody. It doesn't even occur the same way for everybody. Most TSB's are published to show service personnel how to modify components which are OK, but perhaps not fitted correctly and needs to be adjusted correctly. TSB's are in no way an indication that a "flaw" exists. If there is a "flaw" in the design of these transmissions, CPU, or whatever, then why is not a universal occurrence? Why is that a quick fix by the dealer-- an "adjustment" to the CPU--eliminates the hesitation symptom for those who have it done?? That suggests the design of this system allows flexibility. Is this an indication of some kind of flaw? On the contrary, it suggests there's enough flexibility designed into the system to allow changes to be made--if and when needed. Obviously some feel they need it, and the majority don't seem to need it. A design with that kind of flexibility which allows adjustments to owner's individual needs isn't a bad thing!! Perhaps Toyota "got it right" right from the git go?
No, I suspect that Toyota and Lexus are waiting for the EPA, CARB, and the New York state's new CARB agencies to give them leeway to put hundreds of thousands, maybe even millions, of vehicles outside the Fuel economy and emissions specification under which they were originally shipped.
I have no doubt that the transaxle's firmware being all to willing to quickly upshift during throttle closed periods, however brief, resulted in some measurable level of additional fuel economy and lower overall emissions levels.
That's the way the transaxle in my 2001 AWD RX300 works, quickly upshifting, so this upshift firmware design began by 2001 at least.
But that resulted in an inordinate level of wear on the clutches being downshifted into due to the fact that the engine with a hard-wired throttle was already developing torque during the downshift response to follow-on gas pedal application.
So DBW was adopted to "protect the drive train", keep the engine from developing torque until the clutches could be fully and firmly engaged.
And at about the same time upgrading to a 5-speed transaxle which of course added significantly to the firmware's complexity. Now throw in the additional fuel economy requirement of the firmware to select the highest gear ratio possible based on roadspeed and "current" gas pedal (engine torque level "command") position.
And now just as the "proper" downshift is selected and commanded the driver eases the gas pedal farther down just slightly.
Now if left in the previously selected/commanded downshift the engine would most surely lug down and knock/ping so an additional downshift level is quickly selected but cannot be commanded until the previous downshift command has completed.
And just maybe the transaxle's hydraulic control pressure accumulator reserve is exhausted and pressure must be "rebuilt" with the engine still at idle.
All the while the DBW keeps the engine at idle to "protect the drive train".
And now the driver senses the hesitation and applies even greater gas pedal pressure......
We can all be quite certain, safely, that the engine design engineers are very good, even excellent, at their jobs.
But one of the higher, over-riding engine design goals these days is fuel economy and lowering emissions. So by 2004 (RX330) a "lean burn" technique was developed using a higher resolution knock/ping sensor to be certain that NO ENGINE would be subjected to damage due to running the A/F mixture at the new "target", 16:1(?), level.
Look at the fact that many new models now have both intake manifold fuel injectors and high pressure injectors for injecting fuel directly into the compression chamber at or near TDC.
All to provide a stratified charge, RICH A/F mixture surrounding the spark plug, but overall a leaner mixture than could otherwise be used.
That's EXTREME IMMHO!
So for just a few engines all of the tolerances add up on one side, the wrong side, and those engines end up being slightly more prone to knock/ping. No sweat, say the engineers, the new sensor will detect even the slightest level of knocking and the firmware can be designed PRIMARILY to not operate those engines in the parametric regions most subject to causing knocking..
In other words don't enrich the mixture to alleviate pinging (that will get us in DEEP trouble with the EPA, CARB, etc,), just don't lug the engine so far down on the torque curve that it pings.
But I remain convinced that the upshift that occurs in my 2001 RX300 at extremely low speeds, or just before coming to a full stop is there to prevent inadvertent loss of directional control with FWD in case the roadbed happens to be slippery.
I'll warrant the idea of "variations in component tolerances" is worthy of consideration. I've already supported the contention that fuel economy, emission control, and driveline optimization are the underlying reasons why DBW systems behave as they do . I do not, however, agree that a "design flaw" is the root cause of what's being bantied about in this discussion. The fact that an "adjustment" or "reprogrammed CPU" can make the phenomenon go away (ergo, compensate for variations in component tolerances) tells me the design is a good one by virtue of its flexibility, and not "flawed" in any way. On the contrary, it may in fact be better than it is given credit for. The only reason I can think of for those who advocate the "flawed" concept is that it becomes a convenient pretext for dissing the manufacturer.
I happen to have some of the world's absolute best, brightest, programmers working for me, lucky I guess.
I don't think any one of them would content that a fix, TSB, requiring a "reflash" of the non-volatile memory would be the result of anything but a design flaw. When we make a mistake in our software or firmware designs we never hesitate to call it as it is, the previous release contained a design flaw.
I have been a champion of Lexus since my very first one, a new 1992 Lexus LS400, which is still running great at over 100,000 miles. But at the same time I have never been shy about "dissing" them for the design flaws that somehow get incorporated in the vehicle design.
It has been a long road since I started complaining about the design flaws in the automatic climate control in my 92 LS, and generally therefore in all Toyota and Lexus vehicles. Three of the proposals I made back in 1993 to correct these design flaws have now been adopted, two of those in 2001 and the latest in 2005. A few more and "Perfection" will have been fully pursued insofar as automatic climate control system design is concerned.
"..(ergo, compensate for variations in components tolerances)..."
The wide bandwidth high resolution knock sensor signal is the method used to detect, and provide for a method of compensation, for component tolerances.
The firmware's embedded "reluctance" to downshift into the MOST appropreate gear ratio for acceleration torque rather than the gear ratio for the best fuel economy is the design "flaw".
How many of us, driving a manual transmission vehicle, in any of the three known hesitation circumstances described in the TSB, would simply engage the clutch during these inadvertent coastdown periods? The only exception might be if we noticed a need to more rapidly accelerate than would be pertinent in the current gear ratio. In that case a downshift would be the most appropreate move.
So the transaxle doesn't have a clutch...but what harm would come from simply leaving the gear ratio as it is for a few moments during initial coastdown?
Any system that corrupts itself and requires resetting or a cold reboot to resume normal operation cannot be deemed "a good one by virtue of it's flexibility". A robust system is one that operates imperceptibly and with flexibility within normal operating conditions, without requiring the end-user or driver in this case, to significantly change normal behavior to compensate for it's limitations, and certainly one that does not require frequent hard resets or reflashes.
No offense intended for either yourself or Wwest, but I'll stick to my belief: "The only reason I can think of for those who advocate the "flawed" concept is that it becomes a convenient pretext for dissing the manufacturer." Should that be your reason for feeling as you do, all one can say is "to each his own". If it isn't, then you would have to agree that in spite of your feeling as you do, Toyota makes a pretty darn good automobile, flawed or not.
I ORDERED MY AVALON LIMITED WITH A"FACTORY INSTALLED" XM RADIO. WHAT I RECEIVED WAS THE XM BUILT INTO THE JBL SYSTEM, BUT INSTALLED BY SOUTHEAST TOYOTA IN JAX WITH A VERY CHEEZY ANTENNA. THE CAR IS PINE ANT THE ANTENNA IS ABOUT TWO INCHES SQUARE AND ONE INCH HIGH IN BLACK AND MOUNTED ON THE RIGHT EDGE OF THE TRUNK LID WITH THE WIRE RUNNING OVER THE EDGE OF THE TRUNK LID AND DOWN THE INTERIOR OF THE TRUNK HINGE. I WAS EXPECTING A ROOF MOUNT ANTENNA OR AT LEAST A COLOR COORDINATED CENTER TRUNK MOUNT.
You have options. Do a search on Terk XMicro antenna. It is small, and can be mounted inside the car. I have one mounted underneath the windshield - almost invisible - works fine. If you want to, you can get that CHEEZY antenna off your trunk.
Yes, they can be mounted inside the car, but that only works well in cities with ground level repeaters. Once you go out into the country where you are relying only on the satellite for signal, inside mounted antennas behind glass prove inadequate. If you don't want to see the antenna, put it in the windshield wiper bed. On top of the roof is the ideal placement.
Sorry to hear about that. I bought my 2006 LTD here in NY. It came with a small XM antenna mounted on the rear deck right next to the brake (Dole light) light.
I know the topic has focused on the tranny hesitation issue, but my Avalon XLS that I bought in May of 2005 has a continual soft knocking noise at idle, like at a bank window where you get the reflected noise. It is rpm related and not ticky like a lifter that is sticking. More thunk, thunk but soft. I have only got 8000 miles on it. Never had any car act like this....warming it up doesn't make any difference, it stays there until the road noise and unacceptable wind noise drown it out. Is this a problem with the VVI timing (BMW has a problem with VAnos noise that is similar)Is it piston slap, I use premium with no change. This is just not acceptable. I asked the servicce manager if there were any complaints or TSB's about engine noise and he said only tranny hesitation. When I asked how the valves were controlled and motivated, as hydraulic adjusters, buckets and shims, roller cams etc. He seemed lost and thought it was shims in buckets, but with a hydraulic lifter "button" as he called it, underneath. This is obviously a confuscation of his apparent lack of understanding. I am giving it to them next week for a few days to figure it out. But my expectations are low...this car has unacceptable wind noise on both front doors/windows but they couldn't find anything in a full day of riding around with tape on the glass edge of the window. NO smoke test...I found some insulatrion taped to the bottom of the drivers door lead corner (no help). My Highlander is much quieter. The door gaskets are not glued down and are lose...they replaced one but didn't seem to help. Any ideas guys. I really like everything else, but for this money expect engine not to knock and wind noise to be nil at 45-70 mph.
Disagree - I drove across the country in my LTD with the antenna mounted as 3puttmax described (he gave me the idea!). Not once did I lose my signal. zekeman1
Your Avalon sounds like a disaster! Not a great way to enjoy a new automobile, for sure. You must have one of those "one in a million" exceptions, because the majority of reports and surveys state that Avs are consistently quiet and smooth rides. It's unbelieveable your service guy is unable to get those concerns looked after. It isn't rocket science to fix excessive wind noise and improperly attached door seals, nor is it difficult to diagnose an unusual sound coming from an engine (or whatever--it could be something as simple as an exhaust component hitting the underbody!) I would suggest trying a different dealer, and if that doesn't get things done, then contact Toyota's complaint number. We are on our third Avalon (97, 00, and now 05). Every one of them was (is) as quiet as a Church on the road, and the engine at idle was (is) so quiet you'd think it wasn't running! The service rep who you talked to sounds comletely incompetent (hardly possible), if the story is true. There are currently 6 TSBs for the 05 Avalon--only one is for the CPU reflash. Info on Variable Valve technology is easily available through Google or Yahoo. Try this link: http://www.corollaperformance.com/TechInfo/VVTLi.html
Comments
Two questions for you:
1. Have you driven a new Maxima?
2. Have you driven a new Accord?
I guess not because if you had, you would have been silent.
If you don't have the problem then breathe a sigh of relief and realize that you have no factual grounds for comment, however to insinuate that others who have a problem are biased or have some other affliction only serves to demonstrate ignorance.
I have driven both a Maxima and an Accord, and for the record, I've driven an Acura TSX and an TL. Although the Maxima is somewhat more responsive than the Avalon, I suspect that they are simply programming the computer in such a way as to please their target demographics. The TSX and TL perform similarly as the Avalon, and my friend, who is a car enthusiast and a proud owner of a well-maintained TSX, has confirmed that Honda is well-known for their automatic tranny problems, both hardware and computer.
I see no reason to get personal here. People simply notice different things. I have sharp ears, and I probably notice a lot more of the quiet rattles than most of you (being at the age of 23 probably helped). What the Toyota tranny is exhibiting may be by design. Some may argue that it's bad design, but there is the silent majority who think it's working just fine. My dad spent 1000 miles in my Avalon and he loved just how responsive it is compared to his 2001 XLS.
To each his own.
Both are very nice drives. I'll keep the Avalon though.(Our third Av, and and a number of other Toyotas since the 70s.)
You're right. To each his own.
People and dealers appear to making excuses for a transmission or throttle problem. It's not uncommon for dealer to tell false truths to the public about problems. In many cases they refuse to admit that there is a problem.
Does the transmission really hesitate because it’s a learned behavior? Perhaps it needs Prozac in the oil.
Is the alleged problem with the transmission similar to the Lexus transmission issue? I refrained from buying an ES 330 a few years back b/c of the tranny problem and now I find myself doing the same thing on the Avalon .it’s a real shame b/c it's a nice looking car.
What every happened to Japanese quality . :sick:
Some will report experiencing it, others will say it hasn't happened to them.
If human nature holds true, it's likely negatives outnumber positives in these forums because people tend to be more vocal about bad rather than good.
Truth be told, we haven't heard from the million or so who don't participate in these forums.
The very small percentage of yays or nays heard from in these forums is really no valid indication one way or the other.
The closest thing to any form of broad based opinion would be the many positive consumer surveys out there, PLUS the fact that Toyota in general is doing well in the market place. It's probably safe to say the Consumer wouldn't continue to buy anyone's product in such overwhelming numbers if it wasn't good.
As regards your question: "What happened to Japanese Quality?", It could be said that their quality hasn't changed, but the Big Three automakers have learned to do quality better. In other words, the playing field is much more level now than a few years ago. I for one, am glad to see that.
Now, if GM, Chrysler, and Ford can only get their fiscal ships in order......!
I wonder how Lexus corrected this problem on the E-300?
The sample of car owners in this forum is a cross-section of all the cars sold. The people writing here received cars randomly. So this is a sample of the car.
2014 Malibu 2LT, 2015 Cruze 2LT,
Well my friend,, if you truly believe that, then perhaps we should sit down and talk about the bridge I have for sale!!
Go through the old Accord Prob & Solutions. Look at the 03 comments as people bought those and then note what things got changed midyear and for the 04 model...
2014 Malibu 2LT, 2015 Cruze 2LT,
They are not statistically representative of what is really happening in the automotive marketplace.
As an example, take the M&R forum called "Engine Hesitation-All Makes and Models". Nine out of ten posts that forum are by the same 7 or 8 people. All these few individuals talk about is one manufacturer. If one didn't know it was always the same group discussing an issue with that manufacturer,it would be easy to assume the issue was only about a problem with that single manufacturer. But it's not the case. It's a few individuals using that topic to discuss one issue.
Another reason why one cannot assume these forums are reality has to do with what I would call "pseudo posts". It is quite simple for one person to appear in these forums with any number of different usernames. One person using that technique can make it look like many people talking about one single problem; basically manipulating the system for whatever reason. It happens, and I suggest more than enough in spite of Edmund's wishes that it didn't.
So for these and many other reasons it wouldn't be adviseable to assume these forums are anywhere near what the general public thinks or what may really be the case from a consumer viewpoint.
That said, they are often interesting and informative, but absolutely by no means a statistically representative sample of overall consumer opinion.
Assuming anything otherwise would be extremely unwise, if not downright foolish.
I just noticed that there are 6 or 7 spots of discoloration under the clearcoat. These are located above the passenger side doors, along the strip that is just below the roof of the car. They almost look like small irregular pieces of tape on the paint, and then they were clearcoated over. Not a color so much as darker spots. Some the size of a pea, others more elongated, about 1/8" wide and 1/2" long.
The car has about 900 miles and I never notice them until a few days ago. I am sure they were not there before.
You can't clean them off, and they are not dirt, smudges, etc.
Anyone have any ideas?
Still happier than a pig in swill on a hot summer day!
If people are using multiple IDs to sign on, you just send a note to the host. They say they can determine that is occurring.
2014 Malibu 2LT, 2015 Cruze 2LT,
It is a very pretty car but I wanted to mention that for tall drivers (I'm 6'3") visibility is poor. The windshield cuts much too low for me and would require leaning over the steering wheel & dash to see stoplights.
I'm sure it's fine for normal sized folks but wanted to pass along this tidbit of info since most of us haven't had a chance to see the Lucerne yet.
One more off my list...
Tom
Now let's compare it with the CR method. They take random sample of 2005/2006 Avalon owners regardless of the 3 conditions above. So how is forum a good a review as the CR method?
Take some consolation in knowing there are indeed, a vast majority of Av owners out there who are completely satisfied with their rides. Even in this forum, as statistically invalid as it is, the positives far outnumber the negatives.
personally, i would prefer cars with less complexity but this is just a dream: between state,local and federal requirments and the big selling point in the general public for all the gadgets and do-dads, a simpler car with less electronics is just that: a dream.
At this point I don't see how anyone can question whether or not the Toyota and Lexus 5-speed transaxle has a firmware flaw within the engine/transaxle ECU. Such flaw only exhibiting itself under certain unique circumstances. Some of those circumstances are clearly driver action (inadvertent) related but the base flaw lies at Toyota's feet.
It is begining to look as if the problem relates to an attempt to squeeze the highest possible mileage out of the fuel.
All of the vehicles involved seem to have been upgraded to a newly developed wide bandwidth more sensitive non-resonant knock/ping sensor. My guess is that this allows the engine, during cruise, to be operated beyond the standard A/F mixture ratio, 14.7:1, well into the area of leaner mixtures.
Prior to this development the downstream oxygen sensor was the sole feedback source for controlling the mixture ratio, and it would not work either above 14.7:1, or below. Under acceleration or high engine torque the ECU uses the MAF/IAT sensors in order to run the mixture RICH.
With the advent of the new more sensitive knock/ping sensor the mixture can be deterministically "tuned", leaned, in realtime, using the knock/ping sensor to be sure the engine isn't damaged via even the slightest knocking/ping.
So now the engine/transaxle ECU has a "map", detailing the A/F "leaning" level each individual cyclinder can withstand before knocking. Due to the inadvertent uniqueness of each individual engine this map is "learned" after the vehicle leaves the factory, and is likley, of obvious necessaty, continually relearned as you drive.
I now have ~20,000 miles on my manual 6-speed 2001 Porsche C4. Over time "my" ECU has learned just what gear I need to shift down into when I wish to accelerate, slowly or quickly, rapidly, from my current speed to a higher one.
Your Toyota/Lexus engine/transaxle ECU, by factory design, "wants" to be in the highest gear appropreate at any given time based on roadspeed and throttle position.
Remember it's a five speed gearbox, and when you go from closed throttle where is may very likely be in, have shifted into O/D, to open throttle, the ECU must quickly decide "your" intent, all without knowing what's in your mind or seeing the road ahead.
Slowly open the throttle, or open the throttle quickly but to a mid-position and it will always default to the hihest gear that would yeild the best MPG. But now you sense a lack of response to your throttle input and push the gas pedal farther down. Oops, the ECU now wants to put you into third instead of the previously commanded downshift into forth. But now it must want for the downshift into 4th to be complete before commading another downshift.
At this point things within the transaxle may be getting a bit dicey. During the previous coastdown period the engine RPM was dropped to idle so the transaxle's hydraulic fluid pressure pump isn't moving very much fluid. Besides which durimg coastdown the transaxle's line pressure is dropped to an absolute minimum by the ECU inputs to the control solenoid.
So, the initial downshift into 4th may have exhausted the pressure reserve in the accumulator and now the next downshift must be delayed until the pressure is again bult up, with the engine still at idle.
But now guess what?
Just as the downshift into third begins you push the gas pedal to the floor. Oops, again, says the ECU, now I need to be in second....
Clues:
The dealers have told some owners who are experiencing the engine hesiation problem to switch to premium fuel and at least a few of those owners have indicated that helps.
Now that winter, cold weather, is upon most of us some owners are saying the problem is somewhat lessened. Cold weather, denser air, more fuel, less likely to knock.
One owner had the MAF/IAT module changed out and that seemingly cured the problem.
It appears that rapid and quick gas pedal application alleviates the symptoms.
everybody drives differently: when i am approaching an intersection and i am making a left turn across oncoming traffic, i tap my brakes well before the intersection so that i don't upset the balance of the car through the turn at the intersection; this drives the people behind me crazy, since most drivers wait until they are on top of the intersection and then brake. an automatic transmission even with "intelligence" can only do so much when thre's so many variables.
And yes, some vehicle's may keep more that 3 minutes of driving, driving "style" memory. But how would the system react if I suddenly decided to leave my passive driving mode and became aggressive? When I "change" my driving style on the fly it needs to quickly follow my "lead", not lag behind and appear to be indecisive.
Nevertheless, Wwest has suggested some rather serious conclusions, not the least of which in stating there is a "flaw" in the design of the DBW systems used by Toyota in these vehicles. I don't believe this is true, for a variety of reasons. All automakers today are faced with a multiplicity of challenges. First and foremost of these concerns simultanious management of three major variables, fuel economy, emission control, and driveline management of their internal combustion engines. A daunting task, considering stringent State and Federal legislation governing those parameters.
It has been routinely shown the "hesitation" phenomenon being reported affects some but not others. It apparently only occurs under specific driving conditions. It varies in intensity from one owner to another--from barely noticeable to prolonged intervals in a few instances.
Furthermore, it exists in other makes as well.
All of these factors would tend to support that it may be design related but not necessarily a "flawed" design.
Either way, it must be recognised that Wwest has put forth an opinion--his diagnosis and his alone. That doesn't mean his "flaw" concept is correct. There are many different ideas and theories on why this condition gets attention. We have to accept all of them for what they are--opinions and theories. Some day the answer to this question will be known. It should be interesting to see which of the opinions and theories set out in this forum comes closest to the truth.
Meanwhile, the Avalon is a pretty good automobile. On that, almost everyone here agrees.
However, some examination of Toyota's motivations: What did Toyota have - a dynamically unremarkable car based on a car costing several thousand less - and while it was a fine automobile, it had nothing to really separate it (or keep up with)from the competition (Nissan/Infinit and Honda/Acura) - if it ever was to be marketed to anybody under retirement age. Well, the first thing we (Toyota)need - a really high performance engine (a first for Toyota), styling to set it apart, keep those traditional Avalon attributes of comfort and quiet, and, oh by the way, lets put it on the top the heap economy wise. You might be interested to know that the new GS300 continues with the same lower hp drivetrain because had they put the Av engine in that car there would be no reason for the GS430 upgrade - this change postponed until the 4.6 comes out. A marketing decision.
Anyways, IT WORKED - the Avalons that haven't had to be ordered are moving off the lots as fast as any - at prices well above the 'norm'. Don't underestimate the power of the marketing departments - we can say the car has 280 hp and recommend premium fuel - and if, there is resistance to spending the extra 20 cents a gallon, we'll change it to run on regular at 268 hp. If we get too many complaints about electronic transmissions tuned for max economy, what then?
Thanks for the explanation. You described the problem I was having almost exactly. Since the dealer reset the system it is like driving a completely different car. No more hesitation, or "hunting" and now the upshifts and downshifts are precise and at the right time. I just hope it lasts and if not, the dealer has offered to reset it again if needed.
Please repost your message in the Toyota Avalon 2004 and earlier discussion since that is the one that covers your vehicle.
I wish I could move it there for you, but our Move function seems to be on a holiday break lately.
Before deciding on the Avalon I contacted a Lexus dealer and spoke to the sales manager about a new Lexus. I was told they would give me a great deal and wanted to see me. I asked about the hesitation in the transmission and all I got was "O" and thanked me for being interested in their cars and hung up.
Toyota has been aware of the comments and or complaints for a long time. There has been a lot of time to evaluate, confirm, redesign, and ultimalty fix it. I talked to three Toyota dealers and they all are aware of the transmission matter. What will it take to get it right? Is Toyota waiting for the majority of the Avalon owners to complain.
ange1
I question the idea that there may be a "problem" in a classic sense, at all. (NOTE: I'm not questioning those who say they've experienced hesitation --just that what they're experiencing may be more the way their transmission works,and it doesn't feel "right" to them) I also question the idea there's a "flaw" at the bottom of this phenomenon.
People point to the TSB and say it's evidence that a
"problem" or "flaw" exists. But is that a realistic statement? A TSB isn't a Recall. The entire product line isn't affected. Defective components aren't being replaced. The condition doesn't occur for everybody. It doesn't even occur the same way for everybody. Most TSB's are published to show service personnel how to modify components which are OK, but perhaps not fitted correctly and needs to be adjusted correctly. TSB's are in no way an indication that a "flaw" exists.
If there is a "flaw" in the design of these transmissions, CPU, or whatever, then why is not a universal occurrence? Why is that a quick fix by the dealer-- an "adjustment" to the CPU--eliminates the hesitation symptom for those who have it done?? That suggests the design of this system allows flexibility. Is this an indication of some kind of flaw? On the contrary, it suggests there's enough flexibility designed into the system to allow changes to be made--if and when needed. Obviously some feel they need it, and the majority don't seem to need it. A design with that kind of flexibility which allows adjustments to owner's individual needs isn't a bad thing!! Perhaps Toyota "got it right" right from the git go?
I have no doubt that the transaxle's firmware being all to willing to quickly upshift during throttle closed periods, however brief, resulted in some measurable level of additional fuel economy and lower overall emissions levels.
That's the way the transaxle in my 2001 AWD RX300 works, quickly upshifting, so this upshift firmware design began by 2001 at least.
But that resulted in an inordinate level of wear on the clutches being downshifted into due to the fact that the engine with a hard-wired throttle was already developing torque during the downshift response to follow-on gas pedal application.
So DBW was adopted to "protect the drive train", keep the engine from developing torque until the clutches could be fully and firmly engaged.
And at about the same time upgrading to a 5-speed transaxle which of course added significantly to the firmware's complexity. Now throw in the additional fuel economy requirement of the firmware to select the highest gear ratio possible based on roadspeed and "current" gas pedal (engine torque level "command") position.
And now just as the "proper" downshift is selected and commanded the driver eases the gas pedal farther down just slightly.
Now if left in the previously selected/commanded downshift the engine would most surely lug down and knock/ping so an additional downshift level is quickly selected but cannot be commanded until the previous downshift command has completed.
And just maybe the transaxle's hydraulic control pressure accumulator reserve is exhausted and pressure must be "rebuilt" with the engine still at idle.
All the while the DBW keeps the engine at idle to "protect the drive train".
And now the driver senses the hesitation and applies even greater gas pedal pressure......
Overall component tolerances..!
We can all be quite certain, safely, that the engine design engineers are very good, even excellent, at their jobs.
But one of the higher, over-riding engine design goals these days is fuel economy and lowering emissions. So by 2004 (RX330) a "lean burn" technique was developed using a higher resolution knock/ping sensor to be certain that NO ENGINE would be subjected to damage due to running the A/F mixture at the new "target", 16:1(?), level.
Look at the fact that many new models now have both intake manifold fuel injectors and high pressure injectors for injecting fuel directly into the compression chamber at or near TDC.
All to provide a stratified charge, RICH A/F mixture surrounding the spark plug, but overall a leaner mixture than could otherwise be used.
That's EXTREME IMMHO!
So for just a few engines all of the tolerances add up on one side, the wrong side, and those engines end up being slightly more prone to knock/ping. No sweat, say the engineers, the new sensor will detect even the slightest level of knocking and the firmware can be designed PRIMARILY to not operate those engines in the parametric regions most subject to causing knocking..
In other words don't enrich the mixture to alleviate pinging (that will get us in DEEP trouble with the EPA, CARB, etc,), just don't lug the engine so far down on the torque curve that it pings.
But I remain convinced that the upshift that occurs in my 2001 RX300 at extremely low speeds, or just before coming to a full stop is there to prevent inadvertent loss of directional control with FWD in case the roadbed happens to be slippery.
I do not, however, agree that a "design flaw" is the root cause of what's being bantied about in this discussion. The fact that an "adjustment" or "reprogrammed CPU" can make the phenomenon go away (ergo, compensate for variations in component tolerances) tells me the design is a good one by virtue of its flexibility, and not "flawed" in any way. On the contrary, it may in fact be better than it is given credit for.
The only reason I can think of for those who advocate the "flawed" concept is that it becomes a convenient pretext for dissing the manufacturer.
I don't think any one of them would content that a fix, TSB, requiring a "reflash" of the non-volatile memory would be the result of anything but a design flaw. When we make a mistake in our software or firmware designs we never hesitate to call it as it is, the previous release contained a design flaw.
I have been a champion of Lexus since my very first one, a new 1992 Lexus LS400, which is still running great at over 100,000 miles. But at the same time I have never been shy about "dissing" them for the design flaws that somehow get incorporated in the vehicle design.
It has been a long road since I started complaining about the design flaws in the automatic climate control in my 92 LS, and generally therefore in all Toyota and Lexus vehicles. Three of the proposals I made back in 1993 to correct these design flaws have now been adopted, two of those in 2001 and the latest in 2005. A few more and "Perfection" will have been fully pursued insofar as automatic climate control system design is concerned.
"..(ergo, compensate for variations in components tolerances)..."
The wide bandwidth high resolution knock sensor signal is the method used to detect, and provide for a method of compensation, for component tolerances.
The firmware's embedded "reluctance" to downshift into the MOST appropreate gear ratio for acceleration torque rather than the gear ratio for the best fuel economy is the design "flaw".
How many of us, driving a manual transmission vehicle, in any of the three known hesitation circumstances described in the TSB, would simply engage the clutch during these inadvertent coastdown periods? The only exception might be if we noticed a need to more rapidly accelerate than would be pertinent in the current gear ratio. In that case a downshift would be the most appropreate move.
So the transaxle doesn't have a clutch...but what harm would come from simply leaving the gear ratio as it is for a few moments during initial coastdown?
Fuel savings...
A robust system is one that operates imperceptibly and with flexibility within normal operating conditions, without requiring the end-user or driver in this case, to significantly change normal behavior to compensate for it's limitations, and certainly one that does not require frequent hard resets or reflashes.
Should that be your reason for feeling as you do, all one can say is "to each his own". If it isn't, then you would have to agree that in spite of your feeling as you do, Toyota makes a pretty darn good automobile, flawed or not.
CAN ANY ONE COMMENT?
liners -
You have options. Do a search on Terk XMicro antenna. It is small, and can be mounted inside the car. I have one mounted underneath the windshield - almost invisible - works fine. If you want to, you can get that CHEEZY antenna off your trunk.
Max
If you don't want to see the antenna, put it in the windshield wiper bed.
On top of the roof is the ideal placement.
zekeman1
I would suggest trying a different dealer, and if that doesn't get things done, then contact Toyota's complaint number.
We are on our third Avalon (97, 00, and now 05). Every one of them was (is) as quiet as a Church on the road, and the engine at idle was (is) so quiet you'd think it wasn't running!
The service rep who you talked to sounds comletely incompetent (hardly possible), if the story is true.
There are currently 6 TSBs for the 05 Avalon--only one is for the CPU reflash. Info on Variable Valve technology is easily available through Google or Yahoo. Try this link: http://www.corollaperformance.com/TechInfo/VVTLi.html