The proper way is to turn OFF the ignition, restore the powertrain control module (PCM) battery feed, turn OFF the A/C controls, set the parking brake and block the drive wheels, start the engine, ensure that the engine coolant temperature is more than 80°C (176°F), shift the transmission into Drive, allow the engine to idle for 5 minutes, shift the transmission into Park, allow the engine to idle for 5 minutes, and turn OFF the engine for 30 seconds.
By BobGM Specialist
01/11/2022