The best way to keep your 3rd generation (2011, 2012, 2013 & 2014) Kia Optima running reliably is to regularly change the motor oil and replace the filter on the Hyundai Theta II 2.4 liter GDI inline four cylinder engine. Check out my DIY tutorial for the procedure by clicking on the text link or thumbnail image below.
Kia Optima 2.4L Engine Oil Change Guide
