Hi,

One of the annoying things in my NX300 is that while driving at constant speed apr. 50-60 km/h engine RPMs goes too low, (below 1200, to 1100) and I can feel unpleasant vibration on the car.
My guess is also, that it's not healthy for the powertrain.
It doesn't help if I switch the mode to sport.

As I bought it as used car, maybe this is result of transmission's adaptation to previous owner's driving style?
Therefore I wander does the transmission's memory reset would help here ? Haven't checked is this option available in Techstream though, but I've seen some posts on LS's forum about it.

 

Hey, did you ever solve this? Mine has same issue. Even in neutral as I rev from 800 thru to 1500. Rough around 1100

 

Try removing Neg battery terminal for 30mins.
Sometimes helps reset drive modes back to standard.
Then drive it how you want so it learns your driving style.