SonicAnatidae
Seems you and I have very similar situation with our 2018 Sportages. Mine is an LE AWD with the 2.4L GDI Engine purchased at 29K miles four years ago and approaching 96K as of this writing. I did have the Knock Sensor Harness and software upgrade done. Regular oil changes with Mobile Full Synthetic, replaced brakes and tires from usual wear and tear. I use only premium name brand fuels (Shell & BP) with 93 octane rating. I totally baby my car.
On the last oil change I did have my mechanic perform the recommended maintenance along with replacing the spark plugs and performing a GDI engine cleaning service, and holy cannoli's what a difference in power and fuel economy (added 5 mpg). I'd bet if you get this done that rough idle will go away. My mechanic charges $119.00 for the GDI cleaning service which I highly recommend from my experience.
My only gripe is I do go though a couple of quarts of oil in between oil changes. Do you have this issue? My mechanic warned me when I bought the car this would happen. Other than that she purrs like a kitten.
Beatlesguy
