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Comments
The temperature control knob stopped working recently on my Highlander - it is always is the hot setting (i.e. only hot air blows). Regardless of whether the AC is on or off.
I am thinking of replacing the AC/Heater control unit (find a used one) since I have 46K miles, and warranty is expired. Would this fix the problem?
Any thoughts????
Thanks,
Ashok
It may be a stuck valve in the system rather than the control unit.....with the valve stuck open forcing the coolant to always flow through the heater core...
Had this happen on one of my vehicles a few years back and replacing the control unit won't fix it...you have to replace the valve itself (and I don't know if it is integrated with the heater core assembly or not).
HTH
With that thought in mind has any one tried one of the various HP "boost" systems(***) that modify the IAT (Intake Air temperature) signal? These systems seem to falsify the IAT signal in a way that results in running a richer mixture than the optimum insofar as lower emissions levels are concerned.
Seemingly the same effect as using a higher octane in that the engine would be less likely to knock or ping.
***:
[url=http://www.hurricane-horsepower.com]http://www.hurricane-horsepower.com[/url]
Or search on Ebay or google for:
"progressive tuner"
Mine doesn't make a noise but I have never thought it steers easy. But I made the mistake of driving a lexus before I purchased my 03 HL limited.
Also If I drop the steering column all the way down and lock it, It will steer straight down the road regardless of the incline or elevation of the road.
I have to keep it raised almost to the top in order to make it easier to steer.
may be get a discount on the repair. I was thinking your fuel pump maybe going. good luck on the repair
I took it into the dealer and was told that they had to reprogram the transmission and that I need to drive it for several weeks . They felt that this should end the hesitation problems and could affect the gas milage.
Please offer your opinions.
scloutier
TSB #00405
NHTSA Item #10015488
Title: Engine Control Module Calibration: Transmission Shift Feeling Enhancement.
I brought my 05 HL (3500 miles) into the dealer this morning to discuss this TSB with him.
I had a couple of questions:
1. Has this fix been successful? Answer: In many cases, yes.
2. On my son's 04 HL (which doesn't have the hesitation problem), the car hunts between 5th and 4th gear at freeway speeds (and will drop down to 4th at the slightest touch on the accelerator). It's very annoying, and forces my son to take it out of OD most of the time. My 05 doesn't do this. If I apply the TSB ECM recalibration to my car, will this affect the top end transmission response, creating the same problem that my son has? Answer: Don't know, never had anyone mention this side effect.
Another thing to consider. Once the ECM is recalibrated, it CANNOT be undone (i.e., Toyota will not provide a software download to the dealers that will permit them to go back to the original calibration if you're unhappy with the fix).
Because of this, and because the hesitation on my vehicle is not very bad (much less than others that he's seen, according to the service manager that drove my car), I chose not to recalibrate my ECM (I can always apply the new calibration in the future, if things get worse).
Hope this helps.
lovely. i wonder what the rationale is there? maybe they have to die punch some piece of metal in some location indicating that a certain calibration was loaded, but can't unpunch the metal to undocument it when it is removed?
seems silly but the rationale might be that. their position just leads to mistrust - a poor result.
It is when this matter is portrayed as this horrendous "safety" issue that affects all Toyota V6s that it looses it's credibility.
The Toyota V6 5 speed transmissions are on the Lexus RX330, ES330, Highlander and V6 Camrys and I believe the Sienna, some of Toyota's most popular vehicles. There are a LOT of people out there who are perfectly happy and have no problems, like me, my co-workers and your relative. Suggeting that the thousands of owners whose cars run great have been brainwashed is not a good approach. I read where someone else claimed that all the cars had the problem but some people were just too stupid to know they had it. These kind of emotional, unsupported suggestions actually discredit the whole issue, which is unfortunate.
I wish you the best in resolving your dissatisfaction, but if you try to make this out as a huge, across the board safety issue, which it is not, your case will loose a lot of credibility.
also - you've got the manufacturer telling the consumers "this is normal" and "they all do it", when clearly this can't be true.
finally, you've got the issue that everyone seaking to get the behavior fixed has been unsuccessful - in my opinion there is a combination of HW and SW issues, which the manufacturer is trying to mitigate with SW only. it's not likely to work.
we've discussed the issue of hesitation and safety over in the Engine Hesitation (All makes all models).
Many Mfgrs and particularly service depts. use this phrase when they have no idea what the problem might be. Chev., Ford, Nissan, BMW, et.al. We can't hang that tag on Toyota only. My '04 V6 LTD has never had the hesitation problem but that doesn't mean that I don't have empathy for those who do. Any one who believes it is a pervasive problem is wrong IMO. Of course it shouldn't exist for anyone.
it would be rather upfront and refreshing for toyota to document the problem in writing and indicate it is not normal, but that no fix exists. this way people with appreciable hesitation would have a better shot of getting out of their car.
instead, people who are making good faith payments on a defective ride have the additional insults of someone in authority asserting that everything is within design specs. or, they've got people with vehicles not experiencing the problem telling them they are blowing it out of proportion. how exactly can they assert that i wonder?
this system behavior isn't right...but you know what, there are people that will drive the car, experience it, and doubt their own intuition... because they have faith in the manufacturer and the technology, and because someone told them everything is A.O.K.
Early, pre-2000(??), a change was made to increase safety, improve fuel economy and lower the emissions level. That change resulted in premature transaxle failures at 70,000+ miles. Then DBW was adopted and firmware change was made to prevent the engine from developing high torque for acceleration until the transaxle had completed the downshift(s{??}) and clutches were fully and firmly seated.
Just as Toyota has now publically admitted, the 1 (or more??) second engine hesitation delay is to protect the drive train.
Absent the government(s), EPA, CARB, etc, agreeing to not fine Toyota and Lexus for a fix that would undoubtedly reduce the MPG and increase the emissions I doubt if any fix will be forthcoming.
1. All Toyota V6 5speed autos are prone to terrible hesitation. And anyone who is happy with their cars is either: a) Too stupid to know they have a problem, b) Brainwashed or c) Has faith in the manufacturer and the technology, and believes someone who told them everything is A.O.K.
Or,
2. The tens of thousands of people who are perfectly happy with their cars are driving Autos that will experience premature transaxle failures at 70,000+ miles.
So basically, anyone who does not line up with you and complain about their cars are either stupid, brainwashed, gullible or driving a car that is going to breakdown prematurely. Considering that there are indeed tens of thousands of people like me and my coworkers who think are cars drive wonderfully, that is quite an amazing thing to even suggest.
Oh yeah, nobody is blowing THIS out of proportion. I certainly accept the fact that there are some people out there who are not happy with the way their car drives. What I dont understand is the need to try and suggest the ridiculous things I have listed above. It would make any rational person question the entire matter. It does not help your case, even a little.
After reading some of the comments, I drove around trying to see if there was anything I could interpret as hesitation and could find nothing. I am a retired accident reconstructionist and have quite a bit of experience in testing for these things.
My point is, as others have stated, this is not a universal problem. I encourage others to keep at their dealers if they are experiencing a problem; or, if they are not satisfied, find a good independent shop (one with credentials) that will verify their problem in writing and present that to the regional Toyota rep.
And insofar as I know NO ONE has proposed that ALL owners are experiencing this problem. Or for that matter that all vehicles in the category (define it as you will) are subject to the problem.
If it were to become necessary I have no doubt that I could PROVE that the transaxle in my 2001 AWD RX300 exhibits both the "bumped from behind" and the "slingshot effect" symptoms when the transaxle upshifts due to coastdown. Having now driven it ~50,000 miles the effect is un-noticeable to me, it has become commonplace.
And speaking of 50,000 miles I suspect that somewhere in the next few years I will be DIYing the transaxle overhaul and then I will know what failed.
A couple of clues. Toyota has said that the use of premium fuels will help to alleviate the engine hesitation symptom, and I believe a few posters have verified that indeed, it does. Second, on another thread the change out of the MAF/IAT sensor module seemed to completely alleviate the symptom.
According to the MY 2004 Lexus RX330 shop manual the IAT sensor that is an integral part of the MAF module should measure between ~2200 ohms to ~2600 ohms with 68F intake airflow. A 20% tolerance, variation "span". Is that acceptable for a sensor that is integral to controlling the A/F mixture ratio??
Obviously that is enough allowable sensor variation that by pure happenstance some vehicles could be subject to the problem and some not.
And keep in mind that there are three specific instances, well defined by Toyota itself, wherein the engine hesitation symptom is (most) noticeable. I suspect some owners could drive these vehicles for many years and never encounter any of the three circumstances.
Can you verify for us, or not, that you were trained to determine if ABS was involved in the visible skid marks and that ABS activation always resulted in a longer stopping distance? Lower calculated entry speed for a given length of skid marks with ABS than non-ABS?
I'm sure I was told that by someone in your position with WSP, Washington State Patrol, some years ago but maybe I got it wrong or my memory is not as good as I tend to want.
What actually happened is this. Someone with what they perceived as unacceptable hesitation and shifting characteristics went straight to arbitration. They were told by the arbitrator that Toyota needed to be given a chance to correct the problem. Toyota then applied the "shift feeling enhancement" TSB. The customer was also informed by the Toyota service representative that although the TSB addressed some shifting characteristics, that the manufacturer had designed in a slight delay of one second or less to protect the drivetrain. For whatever reason, the customer refused to let the arbitrator actually drive the car so the arbitration was dismissed.
As someone else posted, all cars have a slight delay between pressing on the accelerator and the car moving forward. Some people claim that they have a longer than "slight" delay and want that issue addressed. For them, I wish the very best success with that endeavor. But to make distorted statements like the one above is wrong. The shifting characteristics of my car and others I know are just fine as I mentioned above. To imply otherwise or suggest that Toyota has made some big public admission, which they have not, is just plain untrue.
i don't believe that.
if "you" in your post refers to me (and assuming it does) - consistently i have taken a position not too dissimilar to yours - the vast majority of owners have no issue, experience no hesitation.
something is happening in a percentage of vehicles. here we may disagree. i'm not sure.
you say "I certainly accept the fact that there are some people out there who are not happy with the way their car drives." ... you aren't asserting that they are overly sensitive or something like that are you?
you don't experience hesitation, therefore you conceed there is possibly something wrong with their cars right?
do you think they are lying?
Neither of these cars has any throttle delay, NONE WHATSOEVER. When I press the gas pedal, in gear, out of gear, clutch engaged or no, the engine RPM begins to rise INSTANTLY.
So, clearly, DBW, of itself, is not a part of the engine hesitation problem unless the Toyota/Lexus design engineers wish it to be.
Now, unless you assume that no one of interest of the manufacturer has read or somehow been advised of these statements being passed on to the public why has there been absolutely no form of denial from the manufacturer??
So, the announcement, "the throttle hesitation is there to protect the drive train", has been made available to the "public", and absent a denial from someone in a position to really know, factually, it now stands as a public announcement that is true.
Nor do I think anyone is lying here. I take at face value the claims of the people who are unhappy with their cars and empathize with their situation.
My concern has been the posts that imply that this is a huge, across the board problem that affects all V6 5 speeds, which is obviously untrue. I do believe that the "Toyota Admission" statement I reference above was taken out of context and enhanced for effect.
As far as the built in delay, I have never noticed it. In fact, I believe that even those people who report hesitation issues get good, quick acceleration from a stop. As for other circumstances where the car is in motion at various speeds, I have never noticed any hesitation or unfavorable shifting characteristics. I assume that whatever built in delay there may be, it is basically imperceptible to me.
I understand that for those with a problem, life would be so much easier if everyone reported having the same issue. My comments are not intended however to lessen the importance of anyone's particular issue. Only to put things in perspective.
So why do you feel that there is a need to put things in perspective, again and again??
And think about it a moment, do you really think the factory representative would have made such a statement with the expectation that it would never be passed on to other interested parties...??
Billran is entirely correct about how that oft repeated claim re "protect the drive train......" statement got into these forums.
It was a statement alledged by someone claiming to have been told that by an alledged "Toyota Rep" in an alledged "Arbitration."
That's Hearsay in every sense of the word, and more.
Not only was it an uncorroborated remark, but it was made by an made by an anonymous person about an unproven situation.
Claiming that "It must be true" in the face of "no denial by the manufacturer" is wrong.
Claiming it as a "Public Admission" is also wrong.
It's one thing to allow the benefit of a doubt. Claims like those are so loaded with doubt as to be completely ludicrous.
As another who has no problems with the HL transmission, I support Billran's observations about this issue being blown completely out of context.
Claims like that one certainly don't help those with genuine issues.
Lately I've been kinda sittin' back watching this issue gradually dissolve into itself. Posted at the other topic for a while but cut way back on that too. Wasted too much time. For a while there I was hoping it might change from just a few regulars going on and on about it, but that hasn't happened. Still the same half dozen stalwarts keeping it alive, but not much more.
I'm beginning to think that your term "alleged" is just your polite way of calling someone a liar.
But, be that as it may, please bear with me for a moment in my belief that where there is smoke there is fire. Go along with my assumption, for the moment, that a few owners are actually experiencing the 1 to 3 second delays in the circumstances that Toyota has itself defined within the TSB.
Sorry, I take it for granted that the TSB is correctly stated and constitutes a publically available document. In that they are usually released to Alldata for general public access I guess we might even be free to call the TSB a "public admission" that Toyota, at the very least, admits to a noticeable throttle hesitation in certain instances which they have very well defined. I wonder, does it strike you as somewhat odd that almost all of the posters complaining of this problem, blowing it way out of proportion, describe the same circumstances in which they occur as does Toyota?
I KNOW something is wrong within the transaxle of my 2001 AWD RX300. I own, and have owned, way too many vehicles with automatic transmissions, including not just a few Lexii's, to believe that the fact that my own ATF becoming brownish and smelled burnt at only 40,000 miles is due to anything other than some design flaw.
And then I read the various posts regarding complaints of early, "premature", transaxle failures in my RX series.
Am I thinking straight...???
Yes, 2+2 still equals 4.
Give me the reins, untethered, and I would rewrite the firmware in my RX300 so that it does not upshift during coastdowns.
For some strange reason, seemingly unknowable at this time, Toyota engineers have chosen to keep the upshifting sequence in and use the DBW throttle to delay the onset of engine torque rising.
Also keep in mind that the Lexus shop manual states that it takes a second or so for the transaxle to shift from neutral to "drive", first gear if the vehicle is stopped. So a one second delay isn't all that outlandish if the transaxle happens to have just begun the upshift due to "coastdown" at the very instant the driver depresses the gas pedal again.
And suppose that "depression" is only slight, as well it might be. Hmmm..., no response, give it a tad more gas.... Now the transaxle cannot abort the first downshift, it has to complete that one and only then can the ECU command yet a deeper downshift. One second, two seconds, maybe three.
Up at the top I asked you to suspend your disbelief and accept that some owners are actually experiencing a significant enough throttle delay to cause them concern. Now having done so may I ask you if my thinking is straight in that context alone.
Oh, and standing in my corner I have absolutely no doubt that what was repeated here " the factory rep said" was/is the god-awful truth.
I am not saying that there is no problem at all. I respect that fact that there are people who seem deeply bothered by this issue. It apparently does not bother everyone to the same degree however.
But regarding automobiles and how they behave, some folks are definitely much less fault-tolerant than others. We've all experienced this. It's possible this is part of the issue here, that some people's standards are higher than others. But then, why not? They didn't buy a Daewoo.