2017 Kia Optima
I have 2017 hybrid. At 19,000 ish miles, I had an oil change. The shop pushed "Engine Sludge Treatment," and "Fuel Induction and Injection" services for $500. I declined. The garage claimed these are suggested by Kia, but none of the three is in the owner's manual. My question is are these legitimate services or not? The oil change frequency (5 or 7.5k) is more frequent than my Prius was (that was 10k).