PRODUCT IMPROVEMENT CAMPAIGN NU 2.0L GDI - KNOCK SENSOR DETECTION SYSTEM (KSDS) ECU LOGIC IMPROVEMENT (PI2108) - This bulletin provides information related to a software update to the Engine Control Unit (ECU) to install the Knock Sensor Detection System (KSDS), in order to protect the Hybrid engine from excessive connecting rod bearing damage. This update is for certain 2019-2020MY Optima (JF HEV) and (PHEV) vehicles equipped with Nu 2.0L GDI engines, produced from July 6, 2018 through October 28, 2019.