Hi all, just picked up a 2018 Sport with just 18,000 miles on it CPO from the Hyundai dealer. It's black with premium package - automatic. It's in great shape and in fact I traded in my 2019 Veloster Turbo on it as I needed more room, but wanted the same equipment and engine. The Veloster was a blast to drive, so when I sought out a replacement I knew I wanted this car. Anyway, I've had the car a week and have noticed an issue that I didn't have with my Veloster. I've noticed that under heavy acceleration like passing someone on the highway that the car seems to "surge" back and forth a bit. It doesn't change the RPM's it just feels like it just goes in and out of power a little bit. It doesn't feel normal. It also doesn't seem as quick as the Veloster was even though it's the same engine - yes Elantra weighs more, but just curious. I don't feel like I get that kick-down power or shift-down like when you need to pass someone. I've read online that spark plugs could be the issue with the gap not at .028 or even premium fuel - again both issues I never had with the Veloster. Anyway, I'm going to take it to the dealer soon, but wanted to double check here as well.