Wheel_Man

iTrader: (1)

So, I have a 2001 LS430 with 49K miles and I've noticed that later model LS430's have much better acceleration than mine. When I floor my LS, it seems as though it has no where near the pick-up that the 04-06 LS's have. I am aware that the transmissions are a bit different, but c'mon, seriously? We just took in a 2005 LS430 today on trade today and that thing is WAAYYY faster than mine and I RELIGIOUSLY service my car. It even sounded meaner than mine, like a REAL V-8!!
Any ideas Guys? Just wondering

caddyowner

I would start by driving your car with a heavy foot for a couple weeks and putting on some long highway miles. Your car is 11 years old with only 49K miles - under 4500 miles per year. I suspect most of those miles were put on puttering around town. I suspect that if the car is given some "exercise", it will respond accordingly.

sojah

iTrader: (1)

the first step is to restart it to reset the ecu. disconnect the negative battery terminal for 30 mins.

make sure the seat is in the correct position and that you write down your radio stations cuz they will both be wiped from the memory, but it keeps everything else.

you should notice a difference after this

monrovea

Sojah....What you say is true! It makes a world of difference.

lev00221

iTrader: (28)

The 04-06 LS430's are going to feel quicker because they have an extra gear in the transmission. Much easier to keep the engine in the "sweet spot" of the torque curve when you have a six-speed vs. a five-speed.

The ECU stuff is valid as well.

Slvr surfr

iTrader: (1)

So do you guys recommend doing the battery reset thingy occasionally? Can it be part of a schedule?

Kansas

Any memory stored in the ECU is limited to the a relatively small number of the most recent cycles -- seconds -- not hours, days and certainly not years. The urban legend lives on!

sojah

iTrader: (1)

^ ^ ^,, so please do explain this cuz i am very skeptical in real life so i need to know why this is ^ ^ ^

if i go right now and get in my car and floor it from a stop there will be no tire spin. if i reset the ecu and in say 35 mins do the same thing; after resetting the ecu; i can floor it and spin the tires. this is all the proof i need and until someone can refute these claims that i can prove then its not so much a legend as it is a fact, jack


( i do love the pic by the way , i'm finding it hard not to smile as i look at it)

Kansas

Here is a general article that briefly discusses the limited learning that some EC transmissions can do: http://www.auto-repair-help.com/auto..._transaxle.php

I did not say that your EC transmission has no memory - only that it, like other EC transmissions with this feature, stores information for only a small number of recent shift cycles.

Yes, you could easily notice a difference in the way your transmission shifts immediately after you disconnect/reconnect your car battery.

I probably notice it more than most people since I disconnect car batteries fairly frequently when working on cars. But I also notice that everything is back to normal after driving a few blocks after reconnecting a car battery.

If you have any information documenting that your LS ECT ECU stores shift cycle information for extended periods I would certainly like to see it. I can be convinced of anything with solid evidence.

sojah

iTrader: (1)

so essentially if after resetting the ecu the car shifts much more aggressively, revs higher, and throttle response is much more immediate for a time period of about 2-3 weeks after an ecu reset, this is because the driver is continuing to drive aggressively?

so in your experience the car's increased acceleration/responsiveness is back to normal after a few blocks of driving? and this is on a lexus?

i am contemplating doing an experiment with my car to test this. the only problems I have had in the past with this is that my normal driving commute consists of long stretches of constant speed highway driving. when driving around the city only (previous commute) i have definitely noticed the increased longevity of the ecu reset responsiveness but not as much with my current driving/commuting patterns.

if someone who drives stop and go for their normal driving could help to test this out i can cover the long highway constant speed commuting side

Kansas

Yes, on both Lexus and Toyota vehicles with ECT-i systems. After reconnecting the battery, driveability is normal within a few blocks of stop and go driving if any change is noticeable at all. There has never been a noticeable increase in accelleration/responsiveness after reconnecting a battery - only a return to the previous normal behavior.

"Seat of the pants" tests like you are talking about are not statistically relevant. Do you have any documentation supporting your idea that your ECU has an extensive memory?

I just read through the 63 page automatic transmission diagnosis section of the hard copy official shop manuals for my 2000 LS400 with ECT-i. Disconnecting/reconnecting the battery is not shown as a solution for any of the many transmission problems that can occur. Actually, the only memory that is discussed at all is the shift pattern memory for PWR, Normal and Snow modes.

I'm a scientist. Show me some documentation. Throw me a bone, LOL.

Edit: You might find this tibit interesting since your 05 LS transmission has the AI feature: http://www.lexus.com.bh/technology_e....asp?model=All

sojah

iTrader: (1)

i'm thinking this is what is happening ^ ^ ^. it has been described as making the car feel like it is in power mode when in normal mode after the ecu reset, and i concur.

do you know why i have no documentation¿ cuz i'm not a scientist, even though i play one at work

JamesHuang

iTrader: (1)

All kidding aside, can something else be actually done?

pibob

I'm trying the re set now, just disconnected the neg. terminal. Let you know what happens in 30 minutes to my 04 LS430.

pibob

Well I did the reset and honestly I don't see much of a difference seem to have the same power as before. I leave this power switch on power all the time, could that cause a problem.