Maybe it is just me but sometimes it feels like I get a better rolling launch with ECT PWR Off. Today I was on level ground with a pretty long stretch of road in front of me and with ECT Off while maintaining 30 mph I go WOT and the car surges forward without hesitation as you would expect...violent almost comes to mind. I then turn ECT PWR On and do the exact same thing and it seems like the initial acceleration is not as abrupt (or violent).

I know this is a rather subjective comparison, but I wonder if by having ECT PWR On and one goes to mash the pedal if the ECU is programmed to prevent too much shock on the tranny and allows for some clutch slippage.

Aside from allowing the car to hold gear longer (engine braking) and increasing pedal sensitivity, I don't feel a difference in having ECT PWR on or off. Shift speed appears to be the same and shift points at redline occur with no apparent difference.

This is another reason why I wish we could get the IS350 in a manual, so we could go about our lives with one less choice to make.

 

Probably it leaves the torque converter unlocked longer to let the motor rev into the power band.

It's like dropping the clutch on a stick shift and not giving gas/rev'ing it. It will be an abrupt experience but the motor won't be in the power band to take off.

Yea only part throttle shifts are affected. Later upshifts and later downshifts is the intention.

My wife has pretty much refused to drive the car (I think she's afraid of scratching it.) It would have been nice to have a stick.

 

Also, is it just me or does the car save more gas with ETC ON when you drive hard? I had 4 drags with someone and the computer showed 19mpg, it dropped to 18.8mpg this morning. I had only used 30 miles to the tank so if I drive hard ONCE, it should drop down to at least 14s Weird.