BMW Series 4 2015 Automatic Gasoline mileage: 293 KM Peace be upon you, my dear brother. I have a question and I need help. I bought a used BMW, it has 290,000 kilometers, a 2015 428i Gran Coupe, N20 engine. Unfortunately, I didn't inspect it before buying. After buying it, I accelerated the car, and the car started to malfunction. I got a "Drivetrain" message on the screen, and the car started smoking white, with a slight hint of blue. I took it to a mechanic, and he said I need to change the high-pressure fuel pump. I changed it. After that, he said I need to change the water pump, thermostat, and water reservoir. I changed them. Then he said the engine has pressure, the water hose is clogged, and I need to overhaul the engine, which will be costly. I was shocked and don't know what to do. I need your advice: Is it really necessary to take the engine apart, even though the car is still running but the engine has a noise?