What's with the black smoke from the exhaust pipe of GM Wuling 465 engine?

Black smoke from the exhaust pipe is a mechanical failure of the engine with a rich mixture (1). (2) The fuel pump pressure is too high. (3) The air inlet pipe leaks. (4) Oxygen sensors and wires. (5) Water temperature sensors and wires. (6) Inlet pressure sensor, air temperature sensor and wires. (7) Fuel recovery tank solenoid valve. I hope the examination can help you. I'm not very professional about Wuling and Changan Automobile. High-end cars are my major. It's all cars