The method of cleaning the automobile water tank is as follows: 1. Open the drain plug at the bottom of the radiator and let the coolant flow into the bucket. Coolant should be properly handled to avoid harm to the environment; 2. Close the oil drain plug, fill the radiator with water, then turn on the engine, turn on the heater control system (the heater control valve will open), add the cooling system cleaner, and let the engine idle for 30 minutes (or follow the instructions on the cleaner bottle); 3. Turn off the engine and let it cool for 5 minutes. Drain the liquid from the radiator, then close the oil drain plug, add water to the radiator, and let the engine idle for 5 minutes. Then re-inject 50\/50 water and glycol antifreeze \/coolant compound (using the coolant used in the car before).