Had 2017 Forte at KIA service twice and they don't know what is erong
Sporatically car check engine light will come on solid and begin to run rough. Will loose power and RPM will reve up to 4 or 5. May run this way several miles or just work itself and check engine light will go off. May do again or may not for couple of weeks. Nothing shows under codes. Been to KIA service twice and can't find what is wrong.