1.Carry the smart key or place it inside the vehicle.
2.Make sure the parking brake is firmly applied
3.Place the shift lever in P (Park). Depress the brake pedal fully. You can also start the engine when the shift lever is in the N (Neutral) position.
4.Press the engine start/stop button while depressing the brake pedal.
5.Do not wait for the engine to warm up while the vehicle remains stationary. Start driving at moderate engine speeds. (Steep accelerating and decelerating should be avoided.)
WARNING - Unintended vehicle movement
Never leave the smart key in the vehicle with children or vehicle occupants who are unfamiliar with the vehicle operation. Pushing the engine start/stop button while the smart key is in the vehicle may result in unintended engine activation and/or unintended vehicle movement.

Do not press the ENGINE START/ STOP button for more than 10 seconds except when the stop lamp fuse is blown.
Kia Stinger (CK) 2018-2023 Owner's Manual: Exhaust Emission Control System
Description and operation Description Exhaust emissions (CO, HC, NOx) are controlled by a combination of engine modifications and the addition of special control components. Modifications to the combustion chamber, intake manifold, camshaft and ignition system form the basic control system. These items have been integrated into a highly effective system which controls exhaust emissions while maintaining good drivability and fuel economy.Specifications Specification ▷ 13.5V, 150A Item Specification Rated voltage 13.5V , 150A Speed in use 0 - 18,000 rpm Pin 1 Voltage regulator IC Regulator built in type Default regulated voltage (V) [COM terminal] 14.