GeenIdee

Hello,

I have never noticed a big difference with ECT PWR on or of. Is that normal, something broken?
Drove a toyota century not to long ago and that thing was holding gears while decelerating (with ECT PWR on) and mine doesn't.

The light does turn on, on the cluster. It's a '99 LS.

thanks

Stroock639

yea it's barely a difference honestly... not nearly as big of a difference for instance as hitting the ECT SNOW button

with ECT PWR on i've noticed it does downshift a bit more readily and feel just slightly peppier, but it still upshifts too early (especially out of 2nd when it could really add a bunch of performance by holding that gear longer) and overall hardly changes much

they must've figured it was a low priority for an LS buyer haha

shahnoctis

Doesn't do much but if the placebo effect gets you, then PWR makes you feel like you got the PWR

CELSI0R

Functionally, I've noticed a difference on UCF10s. The transmission holds the gears longer, and is especially useful for climbing steep hills

I can't say I've paid attention to differences in acceleration though. I mostly use the power mode to adjust when I want the transmission to shift

400fanboy

I know the throttle body design is different in earlier cars, I'm not familiar with how those systems work. But in 1998 they changed it to drive by wire and it works quite a bit differently, more like modern cars, with the throttle cable controlling a "sensor" on the throttle body, which then is shoved into the computer, whom turns a servo to open the throttle body. There is no mechanical connection until 75%, where there is a failsafe to open the TB 25% to allow the car to still move. Additionally, the earlier LS400 snow modes can't dumb the throttle down the way the 1998+ is able to. I can floor it in my car and the car accelerates like it only as 50 horsepower because the throttle is only ever actually opened by that 25% from the computer dumbing it down.

Anyway, this is how PWR in my 1998 works:

1) The transmission shift programming changes to a more aggressive map; mostly in that it will hold gears for longer before upshifting given the same throttle position. It also becomes much more willing to kickdown gears when requested (you push the pedal down a bit to overtake. Not flooring it). However, it does not downshift on deceleration like a modern cars sport mode does to keep the RPM in the powerband.

2) The throttle becomes more sensitive. This means that the ECU interprets the signals from the throttle differently, applying more "gain" to the signal. The main result is more throttle (and power) from less pedal input. Most of this gain is between 10 and 50% of the pedal, to give the impression that the car is more peppy without making it a hair-trigger throttle like making the gain high at 0% would do.

This is actually a pretty fun test to run. Get on a empty-ish road in normal mode and maintain idk some fixed speed, 40 or 50 or 60mph. You want to be in 5th gear. Slowly push the throttle down to accelerate, but not enough for the car to downshift a gear. Hold the pedal in that position and quickly switch the car to PWR mode. It will instantly downshift and start accelerating because of the changed transmission and throttle maps. It might take a few tries to get the conditions right. But when you do, you can find these "edges" between the maps where you can get them to show you the difference. Another one would be to maintain some fixed speed in a low gear (select 2 or 3 in your transmission). You want the RPM's to be pretty high, 3 or 4 thousand. And when you switch between the modes, you will feel the throttle pedal become more and less responsive. It's much more noticeable in this configuration with the transmission not being allowed to shift.

CLLEXUSS

I have a 2000, it's definitely noticeable with mine, that is at least I personally definitely notice the difference, that's just me.

Yamae

I usually drive gently and I seldom set the ECT PWR on. But at the long down hills with some slight up and down, the ECT PWR is quite useful for me because I don't need to push the brake pedal often. The engine brake works nicely and the acceleration is better. I'd say it's useful for me. My car is a 5 speeds 98 Celsior.

400fanboy

I usually accomplish that by manually selecting the gear with the gearshifter during hills so that the car doesn't hunt for gears, and like you say Yamae, the engine braking helps save brakes during long downhills.

I actually like using the SNOW program during 0-20 mph stop and go rush hour traffic on the highway. It makes it so much easier to manage the speed of the car and the transmission ends up starting in 2nd which is a LOT smoother. I wish the normal transmission programming did that too unless you actually came to a full stop.

Stroock639

for downhill sections you can use the brake pedal itself to initiate a downshift to 4th + engine braking... you need to be coasting between roughly 40 and 60 mph (by my estimation lol), then just a very light tap on the brake pedal will cause a downshift but only if the hill is sufficiently steep at that moment

and it's definitely engine braking too since you can feel a slight but sudden deceleration and the current reading jumps to 99.9 mpg, i've wondered if this only happens on cars with xenon lights since they have that data from the level sensor

400fanboy

Well you can engine brake in any combustion engine car. It's the result of a fully closed throttle, the engine saps power from its pumping losses. Fuel injection allows the computer to shut off the injectors so it's not really 99.9MPG, it's really infinite at that moment because there (should be) zero fuel being used.



Oh that's quite interesting. However, by that same logic, wouldn't air suspension cars have that as well as they have level sensors right? This being said - I'm not sure how level sensors could determine that. Going up a hill would look the same as traveling on level ground with weight in your trunk.