Jump to content


Calling Wwest!


MotoMac

Recommended Posts

Calling WWest... Below is your final post in the 9 page thread about RX330 (mostly 2004) that had the hesitating transmission problem. This was posted in January 2005.

Actually, this is sent to any and all who may have some info on the problem, not just Mr. West. :)

------------------------------------------------------------

I too was banned, for life, from clubless, mostly because the moderators felt I was unjustly, and too often, denigrating their "beloved". But then I will be 65 this year.

Here is a post from another forum wherein someone was suggesting more frequent fluid changes might be the solution.

I don't think changing the fluid more often will be an effective effort.

The fluid is being "cooked" because something within the transmssion is over-heating. My guess is that that "something" is the bands and clutch surfaces because they are still not fully engaged as the engine builds RPMs and torque when the gas pedal is unexpectedly(***) and agressively depressed.

***The firmware in the transmission ECU is not downshifting from 3rd(?) to first until the vehicle comes to a full and complete stop. Accelerating just before coming to a full stops results in the need to quickly shift from 3rd(?) to 1st, all while the engine is already reacting to a (fully?) open throttle valve.

Except in the 04 or later with an e-throttle. In that case the engine ECU chooses not to "see" the open(ing) throttle until the transmission has shifted into 1st and the bands and clutches are fully seated. That very like takes more than 1.2 seconds, the time the shop manual says it take to shift from neutral when you first move the shifter to D, drive.

Same problem with/during coastdown, the RX transmission upshifts from 3rd to 4th (according to the 01 AWD Lexus shop manual) during coastdown, and now if you suddenlyn decide to accelerate the transmission must quickly shift from 4th to 3rd, or maybe even to 2nd, and while the engine is already building torque....

Except on the 04 or later models with e-throttle.

-------------------------------------------------------------------------

I did a search and came up with the thread with the above message and one other thread with many very similar messages. Unfortunately, they were both several years old and I haven't found anything more recent.

The basic question is: Was there ever any sort of resolution for this problem?

I had heard a little bit about this hesitation problem when I was shopping for a RX last summer, so was careful to pay close attention while doing the test drive. It shifted perfectly, and since everything else on the car was excellent, I bought it. A few days later I shipped it overseas (I'm posted to Kuwait). When it arrived several months later, the battery was dead, but fired right up with a jump and holds a charge just fine now. The first thing I noticed when I finally got the car registered and was able to drive it, was that the idle would jump up to around 1800 rpm within about 5 seconds after the engine was started, and then would gradually return to normal within 3 or 4 more minutes. This is very similar to a carburated engine with an electric choke, but I knew the RX was not so equipped. Also, it most definitely did not do that before it was shipped.

The second thing I noticed was the hesitation in the transmission. As I said above, it hadn't done it when we first bought it, but now it was very noticeable. In the past few months, I've tried to adjust my driving to the transmission, but nothing seems to help....and the problem seems to be constantly changing a bit. It will be fairly nice for a few minutes, then gradually gets worst until it feels almost dangerous, then works its way back to only slightly annoying. The problem seems to lessen slightly when there is more of a load on the engine....i.e. when I have the A/C running.

The lastly, my mileage has been getting progressively worse. It's now down to 18 overall from the original 25-26 overall. I am using 93 octane super unleaded. Most of my trips are short (under 5 miles commute), but at least once a week there is a 45 minute, fairly high speed (80-90 mph) trip. Neither of these two types of trips changes the symptoms.

So, did Lexus/Toyota come up with a fix? Could having the problem show up after the battery ran down have any bearing on the problem? Did the ECU "forget" what it was doing when I first bought it and revert to some older program that has this shifting problem? Or, is there a separate ECU for the transmission (TCU maybe)? Would the strange-acting idle be related to this? Could the decreasing mileage be related? Do I ask too many questions?

I am surprised that the original thread just stopped all of a sudden 3 years ago and hasn't cropped up again (or not that I can find).

Any assistance would be greatly appreciated.

Cheers,

Mac

Link to comment
Share on other sites


When it arrived several months later, the battery was dead, but fired right up with a jump and holds a charge just fine now. The first thing I noticed when I finally got the car registered and was able to drive it, was that the idle would jump up to around 1800 rpm within about 5 seconds after the engine was started, and then would gradually return to normal within 3 or 4 more minutes. This is very similar to a carburated engine with an electric choke, but I knew the RX was not so equipped. Also, it most definitely did not do that before it was shipped.

The second thing I noticed was the hesitation in the transmission. As I said above, it hadn't done it when we first bought it, but now it was very noticeable. In the past few months, I've tried to adjust my driving to the transmission, but nothing seems to help....and the problem seems to be constantly changing a bit. It will be fairly nice for a few minutes, then gradually gets worst until it feels almost dangerous, then works its way back to only slightly annoying. The problem seems to lessen slightly when there is more of a load on the engine....i.e. when I have the A/C running.

The lastly, my mileage has been getting progressively worse. It's now down to 18 overall from the original 25-26 overall. I am using 93 octane super unleaded. Most of my trips are short (under 5 miles commute), but at least once a week there is a 45 minute, fairly high speed (80-90 mph) trip. Neither of these two types of trips changes the symptoms.

So, did Lexus/Toyota come up with a fix? Could having the problem show up after the battery ran down have any bearing on the problem? Did the ECU "forget" what it was doing when I first bought it and revert to some older program that has this shifting problem? Or, is there a separate ECU for the transmission (TCU maybe)? Would the strange-acting idle be related to this? Could the decreasing mileage be related? Do I ask too many questions?

I am surprised that the original thread just stopped all of a sudden 3 years ago and hasn't cropped up again (or not that I can find).

Any assistance would be greatly appreciated.

Cheers,

Mac

Is there a Lexus dealer there?

There was an upgrade program for the CPU. It's possible that if the battery was dead long enough that the CPU "forgot" the re programing.

Most FI unites have a cold start enrichment program that runs a little fast until it warms up.

Link to comment
Share on other sites

Is there a Lexus dealer there?

There was an upgrade program for the CPU. It's possible that if the battery was dead long enough that the CPU "forgot" the re programing.

Most FI unites have a cold start enrichment program that runs a little fast until it warms up.

There is one Lexus dealer here, but I hear really bad things about them. That said, there are probably more Lexus' on the road than any other brand...other than perhap Toyota.

I'll go talk to the service manager at the dealership, but am nervous about the fact that the cars sold here are not U.S. spec. I'm reluctant to get the CPU re-flashed because there might be some things that are different in the programming for U.S.-spec and other-spec cars.

I know about the enrichment devices, but it does it even when the temps are over 90. When I bought it in WashDC last year, it didn't do it at all, even when the temp went down into the 50's overnight.

Guess I've got to bite the bullet and go see the dealer. There's no way I can go 2 years without any service other than what I do myself.

Link to comment
Share on other sites

I did see that thread, but it seemed to only cover up through the 03 model, and my understanding is that the 04 model had a different transmission.

I have been paying a lot closer attention to my driving and how the transmssion reacts. My last car, a Honda CR-V, had an absolute horrible transmission. It was supposed to automatically adapt to the driver's style, but in reality it only adapted to some vague idea of shifting whenever it felt like it. One of the thing I used to do was to lift off the accelerator slightly to let it shift, which really seemed to help make the ride less jerky. I have found myself doing that to the RX without even thinking about it, and it really seems to confuse the transmission. Since the Lexus has such a sweet and fairly high-revving engine compared to the agricultural lump in the Honda, my lifting off to help it shift is definitely not where it is programmed to shift. I've been trying to practice not lifting slightly for shifts and just let the car do what it wants, and that has improved things quite a bit. Even my wife noticed that it was smoother, so that really means it has helped. I don't think this is a cure for the problem, but really does lessen the hunting and delays I had been experiencing, but every little bit helps.

Link to comment
Share on other sites

I've been trying to practice not lifting slightly for shifts and just let the car do what it wants, and that has improved things quite a bit.

Stab and steer. That is the only kind of driving the automatic trans understands. Don't try to "help" it shift. There are way too many factors like the TPS, ECU and other sensors designed to shift under load.

Link to comment
Share on other sites

  • 9 months later...

I did see that thread, but it seemed to only cover up through the 03 model, and my understanding is that the 04 model had a different transmission.

I have been paying a lot closer attention to my driving and how the transmssion reacts. My last car, a Honda CR-V, had an absolute horrible transmission. It was supposed to automatically adapt to the driver's style, but in reality it only adapted to some vague idea of shifting whenever it felt like it. One of the thing I used to do was to lift off the accelerator slightly to let it shift, which really seemed to help make the ride less jerky. I have found myself doing that to the RX without even thinking about it, and it really seems to confuse the transmission. Since the Lexus has such a sweet and fairly high-revving engine compared to the agricultural lump in the Honda, my lifting off to help it shift is definitely not where it is programmed to shift. I've been trying to practice not lifting slightly for shifts and just let the car do what it wants, and that has improved things quite a bit. Even my wife noticed that it was smoother, so that really means it has helped. I don't think this is a cure for the problem, but really does lessen the hunting and delays I had been experiencing, but every little bit helps.

Grouch...

I agree with you! After trying all sorts of things, including driving "softer" or "helping" it shift, I finally gave up and started driving it harder....and that does help. I think this car actually likes to be driven slight more aggressively than one would normally. On top of that, it also seems that my mileage is improved a bit when driving a little harder.

Strange....but more fun!

Cheers,

Mac

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.



×
×
  • Create New...

Forums


News


Membership