 I bought my 2012 Optima LX brand new. Kept up with oil changes and used it almost exclusively for commuting on the highway. Without warning the motor started knocking and squealing on the freeway and then died. Had it towed to KIA who said that the engine needs replacement. Since I am 5,000 miles beyond the 100,000 mile warranty they will not cover anything and gave me a quote of about $7,000 to replace the motor. Although I absolutely loved this car, this is unacceptable. It appears that I am not the only person who has experienced blown engines with the Kia Optima. Now I have a car that is only half way paid for and I have to come up with 7k to fix it.  I will never buy a Kia again.