JDR76

He said he has a 2017 IS300. All 2017 IS300s are AWD V6. If he had the 4 cylinder turbo in a 2017, he would have said he had the IS200t. IS200t RWD was not renamed the IS300 RWD until MY 2018.

arentz07

Thank you!!

Yeah I hadn't thought about the ECU/transmission learning. I wonder how it manages to keep up with all the different people who drive it. (My guess, not that well)

Pretty much everything I have as a loaner feels a bit more touchy than my IS 300 (AWD, to be specific). Mine's always felt that way - smooth and not too touchy, from day one.

EZZ

All the loaners are the lower engine trim variety so all felt sluggish relative to the 350 I have but when I had a G35 coupe, I felt all of the loaner coupes felt faster than mine. I think the adaptive ECU makes this phenomenon common across all makes.

E46CT

Facelift 3IS is roughly 90 lbs heavier.

RayPags

Yes confirming my car is AWD. The comparison is pretty much apples to apples except for trim F-sport versus non F-sport. Should be the exact same engine and tranny in both cars.

RayPags

So the adaptive ECU theory seems to be the best theory of why the loaner felt snappier and more responsive. Kinda makes sense, I wasn't driving the loaner with fuel economy in mind. I'm sure others have done so as well. If this is the case I need to start burying my gas pedal a bit more : ) No problem there.

I wonder if this why when a fresh ECU tune is installed, they recommend certain driving requirements to be adapted during the first 50 miles. In other words working the throttle a bit harder between 3000 and 6000rpm.

RayPags

Seems like we are experiencing the same thing. Smooth and refined is nice, but have to admit the added touchiness and perceived power in the loaner did question my purchase a tiny bit, although I am happy with the 2017 Fsport, my interior is way nicer.

arentz07

FWIW, A) yes, especially the headliner, and B) Sport mode helps with that quite a bit. Especially for me since I don't drive in Sport every day.

redspencer

iTrader: (1)

You can also use Techstream (or an app like "OBD Fusion") to verify that your Knock Correction Learning Factor (KCLV) is at 20+ in order to ensure that your ECU is using its most optimal map. Some engines are "KCLV challenged" and won't provide the optimal fuel/ignition map until you bring the KCLV levels back up.

http://blog.rr-racing.com/news/2017/...on-lexus-ecus/