20 17 why is the chimney black?

20 17 There is black dirt on the exhaust pipe of Teana, which is normal. Usually, the main fuel of a car is gasoline. After a long time of use, black dirt will appear in the exhaust pipe. Solution:

1. Clean the throttle valve, directly remove the engine decorative cover, remove the throttle valve, clean it with special cleaning agent, and then wipe it with cotton cloth.

2. It is to clean up the carbon deposit inside the engine.

3. The third is to clean up the carbon deposit in the oil circuit.