Car is at the dealership now. Has a couple codes P2098 (Downstream Fuel Trim System 2 Lean), P0308 (Cylinder 8 Misfire), and P219B (Bank 2 Air-Fuel Ratio Imbalance). My car was idling rough, struggled to cold start, and was driving rough (felt like I had a flat tire). Anybody have any luck with this? Will update when I hear back from dealership.